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A prospective, multicenter, observational study on quality of life after laparoscopic inguinal hernia repair with ProGrip laparoscopic, self-fixating mesh according to the European Registry for Abdominal Wall Hernias Quality of Life Instrument

      Background

      There is an increasing interest in patient-reported outcome measurement to evaluate hernia operations. Several hernia-specific quality of life (QoL) scales have been proposed, but none are constructed for preoperative assessment.

      Methods

      The European Registry for Abdominal Wall Hernias (EuraHS) proposed the short, 9-question EuraHS-QoL instrument for assessment pre- and postoperatively. The EuraHS-QoL was evaluated in a prospective, multicenter validation study alongside the Visual Analogue Scale, Verbal Rating Scale, and Carolina Comfort Scale (https://clinicaltrials.gov; NCT01936584).

      Results

      We included 101 patients undergoing unilateral laparoscopic inguinal hernia repair with ProGrip laparoscopic, self-fixating mesh. Clinical follow-up at 12 months was 87% complete. The EuraHS-QoL score shows good internal consistency (Cronbach's α ≥ .90), good test-retest reliability (Spearman correlation coefficient r ≥ 0.72), and high correlation for pain with the Visual Analogue Scale, the Verbal Rating Scale, the Carolina Comfort Scale pain scale (r between 0.64 and 0.86), and for restriction of activity with the Carolina Comfort Scale movement scale (r between 0.65 and 0.79). Our results show significant improvement in quality of life at 3 weeks compared with preoperative and further significant improvement at 12 months (P < .05). No late complications or recurrences were recorded. An operation was performed in day surgery (>75%) or with a <24-hour admission (>95%) in the majority of the patients.

      Conclusion

      The EuraHS-QoL instrument is a short and valid patient-reported outcome measurement following groin hernia repair. Laparoscopic inguinal hernia repair with ProGrip laparoscopic, self-fixating mesh results in a favorable outcome and significant improvement of quality of life compared with the preoperative assessment.
      The time when the success of abdominal wall repair was solemnly measured by the rate of recurrences has gone. Although the recurrence rate is still an important outcome measure, many researchers now consider patient reported outcome measurement (PROM) of at least equal importance in evaluating the quality of an operation.
      • Gabriel S.E.
      • Normand S.T.
      Getting the methods right—The foundation of patient-centered outcomes research.
      • Muysoms F.E.
      • Deerenberg E.B.
      • Peeters E.
      • Agresta F.
      • Berrevoet F.
      • Campanelli G.
      • et al.
      Recommendations for reporting outcome results in abdominal wall repair.
      • Ujiki M.B.
      • Gitelis M.E.
      • Carbray J.
      • Lapin B.
      • Linn J.
      • Haggerty S.
      • et al.
      Patient-centered outcomes following laparoscopic inguinal hernia repair.
      This is most relevant when we operate on oligo- or asymptomatic patients. By implantation of a permanent foreign body in the abdominal wall, we risk inducing chronic pain or restriction of the patient's activities and thus impairing the patient's quality of life (QoL).
      To evaluate and measure the QoL outcome of our hernia patients, we need specific QoL questionnaires, because these are more relevant than generic QoL scales, like the Short Form 36, when we are exploring the PROM of patients after a hernia operation.
      • Heniford B.T.
      • Walters A.L.
      • Lincourt A.E.
      • Novitsky Y.W.
      • Hope W.W.
      • Kercher K.W.
      Comparison of generic versus specific quality-of-life scales for mesh hernia repairs.
      • Belyansky I.
      • Tsirline V.B.
      • Klima D.A.
      • Walters A.L.
      • Lincourt A.E.
      • Heniford T.B.
      Prospective, comparative study of postoperative quality of life in TEP, TAPP, and modified Lichtenstein repairs.
      The International Association for the Study of Pain defined chronic postoperative pain, as pain lasting >3 months after an operation.
      • Callesen T.
      • Bech K.
      • Kehlet H.
      Prospective study of chronic pain after groin hernia repair.
      In 1998, Cunningham et al
      • Cunningham J.
      • Temple W.J.
      • Mitchell P.
      • Nixon J.A.
      • Preshaw R.M.
      • Hagen N.A.
      Cooperative hernia study. Pain in the post-repair patient.
      described the Verbal Rating Scale (VRS) to detect the patients with variable degrees of chronic pain. The Visual Analogue Scale (VAS) for pain is another tool often used to evaluate and measure the pain of patients.
      • Loos M.J.
      • Houterman S.
      • Scheltinga M.R.
      • Roumen R.M.
      Evaluating postherniorrhaphy groin pain: Visual Analogue or Verbal Rating Scale?.
      Although pain is an important parameter determining the QoL after a hernia operation, other domains, like restriction of activities and esthetical outcome, are also of importance. In 2008, Heniford et al
      • Heniford B.T.
      • Walters A.L.
      • Lincourt A.E.
      • Novitsky Y.W.
      • Hope W.W.
      • Kercher K.W.
      Comparison of generic versus specific quality-of-life scales for mesh hernia repairs.
      published and validated a hernia specific QoL score, the Carolina Comfort Scale (CCS), to evaluate mesh sensation, pain, and movement limitation after hernia repair.
      At the same time, Fränneby et al
      • Fränneby U.
      • Gunnarsson U.
      • Andersson M.
      • Heuman R.
      • Nordin P.
      • Nyrén O.
      • et al.
      Validation of an inguinal pain questionnaire for assessment of chronic pain after groin hernia repair.
      validated the Inguinal Pain Questionnaire, evaluating pain and difficulties in performing activities after groin hernia repair.
      • Fränneby U.
      • Gunnarsson U.
      • Andersson M.
      • Heuman R.
      • Nordin P.
      • Nyrén O.
      • et al.
      Validation of an inguinal pain questionnaire for assessment of chronic pain after groin hernia repair.
      In 2011, the same Swedish group from the Karolinska Institute published and validated the Ventral Hernia Pain Questionnaire to evaluate QoL after ventral hernia repair.
      • Clay L.
      • Fränneby U.
      • Sandblom G.
      • Gunnarsson U.
      • Strigård K.
      Validation of a questionnaire for the assessment of pain following ventral hernia repair: The VHPQ.
      In 2012, a working group of the European Hernia Society (European Registry for Abdominal Wall Hernias [EuraHS]) developed an online platform for registration and outcome measurement in hernia operations.
      • Muysoms F.
      • Campanelli G.
      • Champault G.G.
      • DeBeaux A.C.
      • Dietz A.
      • Jeekel J.
      • et al.
      EuraHS: The development of an international online platform for registration and outcome measurement of ventral abdominal wall hernia repair.
      A hernia-specific QoL—the EuraHS-QoL score—was constructed and included in the online registry.
      The reason to develop a new QoL instrument instead of using an existing one is 4-fold: (1) we wanted to develop an instrument that can be used both pre- and postoperatively, which none of the existing scores can; (2) we wanted our EuraHS platform, and thus the QoL score, to be free of charge for users; (3) we wanted to develop a PROM that uses considerably fewer questions; and (4) we wanted to create an instrument that can be used both in groin and ventral hernia patients.
      The EuraHS-Qol instrument is a patient self-reported questionnaire that asks only 9 questions across 3 domains: pain, restriction of activities, and cosmetic discomfort. The questions were chosen in consensus among the 14 members of the EuraHS working group, who come from 9 different countries. The working group tried to select questions that seemed most relevant for QoL before and after hernia repair.
      Recently, Knox et al
      • Knox R.D.
      • Berney C.R.
      A preoperative hernia symptoms score predicts inguinal hernia anatomy and outcomes after TEP repair.
      used a modified CCS (MCCS) to omit questions about the sensation of mesh, adding to the value of a QoL score that can also assess patient preoperatively.

      Objectives

      The objectives of this study were to validate the EuraHS-QoL in patients undergoing groin hernia repair by comparing the instrument with the VRS, the VAS for pain, and the CCS and to prospectively evaluate the outcome at 12 months after laparoscopic repair of groin hernias with a novel mesh, the ProGrip laparoscopic, self-fixating mesh (Medtronic, Minneapolis, MN).

      Methods

      Study design

      A consecutive cohort of patients scheduled to undergo unilateral inguinal hernia repair by laparoscopy was included in a prospective, multicenter study that focused on several methods of preoperative and postoperative QoL assessment. Demographics, indication data, and short-term complications were documented. All patients were invited for a clinical follow-up at 3 weeks, 3 months, and 12 months after the operation. The test-retest was performed at 12 and 13 months by giving the patients QoL forms to be completed at home and sent to the trial secretariat by mail 1 month after the 12-month clinical visit.

      Setting

      The study was conducted at the surgical departments of Maria Middelares Hospital in Ghent, Belgium; Heilig Hart Hospital in Mol, Belgium; and the Ghent University Hospital. The ethical committees of the different hospitals approved the study protocol, with the leading ethical committee at the Ghent University Hospital, Belgian Trial number: B670201317527. The study was registered as NCT01936584 (https://clinicaltrials.gov) on September 2, 2013, with the acronym LIQUOR study (Laparoscopic Inguinal Hernia Repair Quality of Life Research).
      The study cohort was treated between October 2013 and May 2014. Data collection was performed on paper case report forms (CRF) by the principal investigator of each center prospectively. The CRFs were collected and checked for missing values by the study coordinator at on-site visits during the inclusion and follow-up period. The database was closed on September 30, 2015, and submitted to an independent statistician for analysis.

      Inclusion criteria

      All adult patients >18 years with a primary, unilateral, inguinal hernia who planned to undergo a laparoscopic hernia repair were eligible for the study.

      Exclusion criteria

      Patients excluded from participation were: patients with recurrent or incarcerated hernias, patients undergoing combined operations, pregnant women, patients with an American Society of Anesthesiologists score of 4 or higher, patients unable to understand the QoL questionnaires, and those patients choosing not to participate by not signing the informed consent.

      Operative technique

      The laparoscopic groin hernia repair technique was left to the preference of the surgeon and was a 3-trocar technique, either by transabdominal preperitoneal approach (TAPP) or by a total extraperitoneal approach (TEP). An operation was planned either as an outpatient procedure or with a 24-hour hospitalization, depending on the general condition or age of the patient and on the patient's preference. Operations were performed under general anesthesia. A single 2-gram dose of the antibiotic prophylaxis cefazoline (Cefacidal, Bristol-Myers Squibb, Braine-l'Alleud, Belgium) Cefacidal was administered at the induction of anesthesia.
      After dissection of the preperitoneal plane and reduction of the hernia, the ProGrip laparoscopic, self-fixating mesh was positioned covering the myopectineal orifice. This mesh is a monofilament, polyethylene terephthalate, macroporous textile with the addition of slowly absorbable microgrips made of monofilament polylactic acid. The microgrips give the mesh a self-fixating property onto the abdominal wall on one side of the mesh in a manner similar to the Velcro fixation technology for shoes.
      The ProGrip laparoscopic, self-fixating mesh is preshaped to fit the inguinal anatomy: the inguinal fold and the angle between the iliac vessels and the anterior abdominal wall. The mesh used in the study was 15 cm in width and 10 cm in height, and the cranial part of the mesh was covered on the nongripping side with a rapid absorbable collagen film to ease the mesh placement and intraoperative handling. It may be stated that the self-fixating properties of the mesh omit the need for fixation with staplers or glue.

      Variables

      Patients’ demographics and hernia variables were recorded prospectively. Inguinal hernias were classified using the European Hernia Society classification.
      • Miserez M.
      • Alexandre J.H.
      • Campanelli G.
      • Corcione F.
      • Cuccurullo D.
      • Pascual M.H.
      • et al.
      The European hernia society groin hernia classification: Simple and easy to remember.
      Operative time, postoperative complications, and hospital stay were recorded at discharge, and patients were planned for clinical follow-up visits with the surgeon at 3 weeks, 3 months, and 12 months postoperatively. Patients were interviewed, and the surgeon did a physical examination to document complications or recurrence. At fixed time points pre- and postoperatively, the QoL was evaluated with 4 different questionnaires.

      Visual Analogue Scale for pain

      The VAS score is recorded by asking the patient to mark on a calibrated, 10-cm line the amount of pain experienced.
      • Loos M.J.
      • Houterman S.
      • Scheltinga M.R.
      • Roumen R.M.
      Evaluating postherniorrhaphy groin pain: Visual Analogue or Verbal Rating Scale?.
      The left side of the line indicates “No pain” and the right side “The worst imaginable pain.” The VAS is measured as cm (range: 0–10 cm) by measuring the distance from the left side of the line. In the LIQUOR study, the VAS for pain was measured preoperatively, 6 hours after the operation and again at 3 weeks, 3 months, and 12 months.

      Verbal rating scale for pain

      The patient is asked to grade the level of pain experienced in 4 levels defined by Cunningham et al
      • Cunningham J.
      • Temple W.J.
      • Mitchell P.
      • Nixon J.A.
      • Preshaw R.M.
      • Hagen N.A.
      Cooperative hernia study. Pain in the post-repair patient.
      : “No pain” = no discomfort experienced; “Mild pain” = occasional pain or discomfort that did not limit activity, with a return to prehernia lifestyle; “Moderate pain” = pain preventing return to normal preoperative activities; or “Severe pain” = pain that incapacitated the patient at frequent intervals or interfered with activities of daily living. In the LIQUOR study, the VRS for pain was measured postoperatively at 3 weeks, 3 months, and 12 months.

      Carolina Comfort Scale

      The CCS has been developed as a questionnaire to assess the QoL of patients that had a hernia repair using a prosthetic material.
      • Heniford B.T.
      • Walters A.L.
      • Lincourt A.E.
      • Novitsky Y.W.
      • Hope W.W.
      • Kercher K.W.
      Comparison of generic versus specific quality-of-life scales for mesh hernia repairs.
      • Belyansky I.
      • Tsirline V.B.
      • Klima D.A.
      • Walters A.L.
      • Lincourt A.E.
      • Heniford T.B.
      Prospective, comparative study of postoperative quality of life in TEP, TAPP, and modified Lichtenstein repairs.
      The questionnaire contains 23 questions with a 6-point scale from 0–5 that reports sensation of the mesh, pain, or movement limitation for 8 different activities. Added to the numerical scale is a descriptive scale: 0 = no symptoms, 1 = mild but not bothersome symptoms, 2 = mild but bothersome symptoms, 3 = moderate and/or daily symptoms, 4 = severe symptoms, 5 = disabling symptoms.
      The total score ranges from 0–115, with a low score indicating a favorable QoL evaluation. The questions are grouped in 3 subscales: “Sensation” (range 0–40), “Pain” (range 0–40), and “Movement” (range 0–35). In the LIQUOR study, the Dutch version of the CCS was used at 3 weeks, 3 months, 12 months, and 13 months. For preoperative assessment with the CCS, we asked the patients to report the 8 questions in the domain of sensation as “not applicable.” This gives a Modified Carolina Comfort Scale (MCCS) with a range of 0–75, which was also recently used and published by other authors.
      • Knox R.D.
      • Berney C.R.
      A preoperative hernia symptoms score predicts inguinal hernia anatomy and outcomes after TEP repair.
      • Wennergren J.E.
      • Plymale M.
      • Davenport D.
      • Levy S.
      • Hazey J.
      • Perry K.A.
      • et al.
      Quality-of-life scores in laparoscopic preperitoneal inguinal hernia repair.

      European Registry for Abdominal Wall Hernias Quality of Life score

      The EuraHS-QoL score is a hernia specific questionnaire with 9 questions that can be scored by the patient in an 11-point scale from 0–10. The EuraHS-QoL questions are divided in 3 domains: “Pain” (range 0–30), “Restriction of activities” (range 0–40), and “Esthetical discomfort” (range 0–20). The total score ranges from 0–90, with the lower scores being the most favorable outcome. In the LIQUOR study, the Dutch version of the EuraHS-QoL score was used preoperatively, at 3 weeks, 3 months, 12 months, and 13 months. The English preoperative questionnaire is shown in Fig 1.
      Figure thumbnail gr1
      Fig 1Example of the EuraHS-QoL score for preoperative assessment of hernia patients in the English language. (Color version of this figure is available online.)

      Bias

      Surgeons with a preference for laparoscopic repair of groin hernias recruited the patients. Patients with large irreducible scrotal hernias and patients with previous operation in the retro-pubic plane (eg, abdominal prostatectomy) were selected for open operative repair. Patients with recurrences after previous repair and incarcerated cases were not included in the study. Therefore, a selection bias toward patients with noncomplicated groin hernias is present. Our follow-up rate of 87% is high, but it might be that patients lost to follow-up either have very bad outcome and therefore refuse to continue follow-up, or they might have very favorable outcome and therefore do not see the need to come for follow-up visits. For each of the outcome measurements (VAS, VSR, CCS, and EuraHS-QoL), an additional full record analysis was performed, including only patients with complete response at all follow-up visits. The results from this analysis were virtually identical to those from the all-data analysis.

      Study size

      In the study protocol, a sample size of 100 patients was empirically chosen as a population large enough to investigate our objective of validating the EuraHS-QoL score and small enough to complete the study in a reasonable time frame.

      Quantitative variables

      Our observations and measurements resulted either in a numeric score (VAS for pain, CCS and MCCS, EuraHS-QoL score) or in a categorical score (VRS). The VRS is described as the percentage of patients reporting each category for level of pain. The VAS score for pain (cm) is described by the mean value and the median value with interquartile ranges (IQR) for each evaluation time point. Because of the tendency of the VAS score toward zero, we also expressed the outcome as the percentage of patients who reported a VAS for pain of zero.
      The CCS is recorded according to the coding scheme available from the CCS User's Guide. Results are reported as mean value and the median value with IQR for each time point. Results are given for the total score, the sensation scale, the pain scale, and the movement scale. Because of the tendency of the CCS to go toward zero, we also reported the 90th percentile at each time point.
      The EuraHS QoL score is reported by the mean value and the median with IQR. Numbers are reported for the overall score (9 questions), the pain domain (3 questions), the restrictions domain (4 questions), and the cosmetic domain (2 questions). The calculation is made as the sum of the scores for the different questions in each domain or overall.
      Coding for “missing” or “not applicable” values of the EuraHS-QoL was done as follows. (1) For the pain domain, if 1 value was missing, it was replaced by the mean of the values for the other 2 questions of the pain domain; if 2 or 3 values were missing, the domain score was considered missing. (2) For the restrictions domain, if 1 or 2 values were missing, the value(s) was replaced by the mean of the values for the 2 or 3 other questions of the restrictions domain; if 3 or 4 values were missing, the domain score was considered missing. (3) For the cosmetic domain, if 1 value was missing, it was replaced by the value for the other question of the cosmetic domain; if 2 values were missing, the domain score was considered missing. (4) For the overall score, if 1 domain score was missing, it was replaced by the mean of the values for the 2 other domains; if 2 domain scores were missing, the overall EuraHS-QoL score was considered missing.

      Statistical methods

      The distributions of patient characteristics and outcomes were summarized using proportions, means, standard deviations, medians, IQRs, and the 90th percentile. Differences in dichotomous and categorical variables between time points were evaluated according to the Fisher exact test. Estimated changes (and their statistical significances) in VAS scores and EuraHS-QoL scores in comparison to preoperative, 3-week, and 3-month assessments, respectively, were obtained from mixed model analyses taking into account individual profiles. The Cronbach's alpha was used to assess the internal consistency of both CCS and EuraHS-QoL instruments. A threshold of .80 was considered an indication of good internal consistency and a value > .90 was considered excellent.
      Test-retest reliability was evaluated by correlating scores obtained at 12 months and 13 months, according to Spearman correlation coefficients. Systematic differences were studied by calculating the mean test-retest bias (+95% confidence interval) and testing its significance according to the Wilcoxon signed rank test. Convergent validity was studied by calculating Spearman correlation coefficients for the agreement of pain subscales of both the CCS and EuraHS-QoL instruments with the VRS and VAS pain scales. Finally, we also evaluated the congruence of the EuraHS-QoL restriction scale and the CCS movement scale. All analyses were performed using SAS software (release 9.4; SAS Institute, Inc, Cary, NC).

      Results

      Participants

      A total of 109 eligible patients were included in the study and signed the informed consent. The flow diagram of the study cohort is shown in Fig 2. After exclusion of 8 patients, 101 patients were operated on according to the protocol with a unilateral ProGrip laparoscopic, self-fixating mesh. We excluded 3 patients during the data analysis because of concomitant disease interfering with the pain and QoL measurements: acute appendicitis, gallbladder resection, and fibromyalgia. Follow-up for 12 months was completed for 88 patients (87%).
      Figure thumbnail gr2
      Fig 2Flow diagram of the LIQUOR study, a prospective validation study for the EuraHS-QoL score, in patients undergoing unilateral laparoscopic groin hernia repair.

      Descriptive data

      Patient data at baseline, operative data, and postoperative complications are described in Table I. The large majority of patients (98%) were treated either in day clinic (76%) or with a 24-hour admission (22%). One patient had an intraoperative bladder lesion during preperitoneal dissection that was sutured and for which a bladder catheter was maintained 2 days postoperative. No readmissions after discharge from the hospital were reported. No late complications or recurrences were reported with 12-month follow-up.
      Table IPatient data at baseline, operative data, and postoperative complications of 101 patients included in the LIQUOR study, a prospective validation study for the EuraHS-QoL score, in patients undergoing unilateral laparoscopic groin hernia repair
      % (n/N)
      % (n/N), n = number of patients/N = total number of patients.
      or Mean (SD)
      Mean value of variable (standard deviation).
      Age (at the time of operation), y56 (14.9)
      Women6% (6/98)
      Body mass index (kg/m2)
       <2557% (58/101)
       25–3038% (38/101)
       ≥305% (5/101)
       Mean (SD)25 (2.9)
      Preoperative symptoms
       Pain80% (80/101)
       Esthetic discomfort12% (12/101)
       Asymptomatic14% (14/101)
      Side of hernia
       Left45% (45/98)
       Right55% (53/98)
      Operative technique
       TAPP36% (36/101)
       TEP64% (65/101)
      EHS hernia classification
      Classified according to the European Hernia Classification.
       Lateral76% (74/97)
      L140
      L230
      L34
       Medial32% (31/97)
      M113
      M215
      M33
       Femoral3% (3/97)
      F13
      Duration of operation (min)43.9 (16.8)
      Time needed to place the mesh (min)5.2 (5.1)
      Intraoperative complications
       Hemorrhage3
       Peritoneal tears during TEP2
       Bladder perforation1
       Conversion to open operation0
      Hospital stay
       Day clinic76% (77/101)
       1-night stay22% (22/101)
       >24 hours2% (2/101)
      Postoperative complications3 weeks3 months12 months
      Seroma610
      Hematoma200
      Operative site infection000
      Recurrence000
      EHS, European Hernia Society; SD, standard deviation.
      % (n/N), n = number of patients/N = total number of patients.
      Mean value of variable (standard deviation).
      Classified according to the European Hernia Classification.

      Outcome data

      The outcome measurements of the different QoL assessments are described in Table II, Table III. The VRS showed a significant decrease over time in the reporting of pain (P = .031). Only 1 patient reported moderate pain, and no patient reported severe pain 12 months after the operation.
      Table IIOutcome of measurement of the VAS for pain, the VRS, and the CCS of 101 patients included in the LIQUOR study, a prospective validation study for the EuraHS-QoL score, in patients undergoing unilateral laparoscopic groin hernia repair
      Preoperative
      Modified CCS (omitting the Sensation scale).
      Time postoperativeSignificance
      Significance according to Fisher exact test.
      6 h3 weeks3 months12 months
      Verbal Rating Scale
       No pain67%77%85%P = .031
       Mild pain24%17%14%
       Moderate pain9%6%1%
       Severe pain0%0%0%
      VAS for pain
       Mean2.02.60.90.60.3
       Median (IQR)
      Median values (IQR = 25th–75th percentile).
      1 (0–3)2.5 (1.5–4)0.5 (0–1)0 (0–0.5)0 (0–0)
       % patients with VAS = 029%11%43%65%76%
      Δ score
      Difference in mean VAS score for time points (standard error).
       Preoperative0+0.5 (0.3)

      P = .03
      −1.1 (0.2)

      P < .0001
      −1.5 (0.2)

      P < .0001
      −1.6 (0.3)

      P < .0001
       3 weeks0−0.4 (0.15)

      P = .010
      −0.6 (0.13)

      P < .0001
       3 months0−0.2 (0.12)

      P = .15
      CCS
       Total score/75/115/115/115
      Mean20.010.93.92.0
      Median (IQR)17 (6–23)4 (0–16)0 (0–4)0 (0–1)
      P904230143
       Sensation scale/40/40/40
      Mean3.41.10.6
      Median (IQR)0 (0–5)0 (0–1)0 (0–0)
      P9012.541
       Pain scale/40/40/40/40
      Mean10.64.21.40.9
      Median (IQR)10 (3–16)1 (0–6)0 (0–0)0 (0–0)
      P902313.552
       Movement scale/35/35/35/35
      Mean9.43.21.40.4
      Median (IQR)7 (1–15)0 (0–5)0 (0–0)0 (0–0)
      P90211141
      P90, 90th percentile.
      Significance according to Fisher exact test.
      Median values (IQR = 25th–75th percentile).
      Difference in mean VAS score for time points (standard error).
      § Modified CCS (omitting the Sensation scale).
      Table IIIOutcome of measurement of the EuraHS-QoL score of 101 patients included in the LIQUOR study, a prospective validation study for the EuraHS-QoL score, in patients undergoing unilateral laparoscopic groin hernia repair
      EuraHS-QoL scorePreoperativeTime postoperative
      6 h3 weeks3 months12 months
      Total score/90/90/90/90
       Mean22.07.23.82.4
       Median (IQR)
      Median values (IQR = 25th–75th percentile).
      22 (9–31)4 (1–10)1 (0–3)0 (0–2)
       P9039191310
      Pain domain/30/30/30/30
       Mean6.22.21.30.7
       Median (IQR)6 (2–9)1 (0–3)0 (0–1)0 (0–0)
       P9013662
      Restrictions domain/40/40/40/40
       Mean9.83.51.61.0
       Median (IQR)9 (3–15)1 (0–4)0 (0–1)0 (0–0)
       P9021864
      Cosmetic domain/20/20/20/20
       Mean6.11.50.90.7
       Median (IQR)6 (2–10)0 (0–2)0 (0–1)0 (0–0)
       P9012422
      Total score
       Δ score
      Δ score = difference in mean EuraHS-QoL score for time points (standard deviation).
      Preoperative0−14.5 (1.5)

      P < .0001
      −17.8 (1.6)

      P < .0001
      −19.3 (1.6)

      P < .0001
      3 weeks0−3.3 (0.1)

      P = .0013
      −4.8 (0.9)

      P < .0001
      3 months0−1.5 (0.7)

      P = .027
      Pain domain
       Δ score
      Preoperative0−3.8 (0.5)

      P < .0001
      −4.7 (0.6)

      P < .0001
      −5.3 (0.6)

      P < .0001
      3 weeks0−0.9 (0.4)

      P = .020
      −1.5 (0.3)

      P < .0001
      3 months0−0.6 (0.2)

      P = .013
      Restrictions domain
       Δ score
      Preoperative0−6.1 (0.8)

      P < .0001
      −7.9 (0.9)

      P < .0001
      −8.6 (0.9)

      P < .0001
      3 weeks0−1.8 (0.6)

      P = .0015
      −2.5 (0.5)

      P < .0001
      3 months0−0.7 (0.4)

      P = .076
      Cosmetic domain
       Δ score
      Preoperative0−4.6 (0.6)

      P < .0001
      −5.2 (0.6)

      P < .0001
      −5.4 (0.5)

      P < .0001
      3 weeks0−0.6 (0.2)

      P = .012
      −0.8 (0.3)

      P = .012
      3 months0−0.2 (0.3)

      P = .41
      P90, 90th percentile.
      Median values (IQR = 25th–75th percentile).
      Δ score = difference in mean EuraHS-QoL score for time points (standard deviation).
      The VAS for pain showed a significant increase 6 hours postoperatively compared with the preoperative pain score (P = .03). But further postoperatively, VAS for pain showed a highly significant decrease compared with the preoperative score (P < .0001). VAS for pain after 3 months and after 12 months was also significantly lower than after 3 weeks. After 3 months, the greater decrease in VAS at 12 months was not statistically significant (P = .15).
      The CCS showed a decrease over time compared to the preoperative assessment with the MCCS. After 12 months, the 90th percentile for the overall score was 3/115, and for the pain scale, it was 2/40. After 12 months, no patient showed a score higher than 4, defined as severe or disabling discomfort, on any of the 23 questions.
      The EuraHS-QoL score showed a highly significant decrease for all postoperative measurements compared with the preoperative scores, not only for the total score but also for the pain domain, the restriction domain, and the cosmetic domain. The EuraHS-QoL score after 3 months and after 12 months was also significantly lower than after 3 weeks for all 3 domains and for the overall score. After 3 months, the greater decrease in the EuraHS-QoL score at 12 months was statistically significant for the overall score and the pain domain but not for the restriction domain at 12 months (P = .076) or for the cosmetic domain (P = .41). The evolution over time of the EuraHS-QoL score is graphically depicted in Fig 3.
      Figure thumbnail gr3
      Fig 3Graphical presentation of the evolution over time of the EuraHS-QoL score of 101 patients included in the LIQUOR study, a prospective validation study for the EuraHS-QoL score, in patients undergoing unilateral laparoscopic groin hernia repair. It shows a highly significant decrease for all postoperative measurements compared with the preoperative scores, not only for the total score but also for the pain domain, the restriction domain, and the cosmetic domain.

      Main results

      The results of the measurements of the internal consistency for the EuraHS-QoL score and the CCS, the test-retest reliability of the EuraHS-QoL score, and the CCS are shown in Table IV. Moreover, these results show the convergent validity for the EuraHS-QoL pain scale, the CCS pain scale, the VAS for pain, the VRS, and the convergent validity for the EuraHS-QoL restriction scale with the CCS movement scale.
      Table IVResults of a prospective validation study for the EuraHS-QoL score, in 101 patients undergoing unilateral laparoscopic groin hernia repair, showing the measurements of the internal consistency, the test-retest reliability, and the convergent validity for the EuraHS-QoL, the VAS for pain, the VRS, and the CCS
      Internal consistency
      Cronbach's alpha
      Preoperative
      Modified CCS (omitting the Sensation scale).
      3 weeks3 months12 months13 months
      CCS
       Sensation scale.96.91.89.97
       Pain scale.94.95.97.95.96
       Movement scale.95.93.94.93.95
      EuraHS-QoL
       Pain scale.83.87.92.90.89
       Restriction scale.92.96.94.91.93
       Cosmetic scale.95.92.95.90.92
      Test-retest reliability
      Test-retest
      Difference 12 and 13 months

      mean (95% CI)
      Significance
      According to the Wilcoxon signed rank test.
      Spearman correlation
      CCS
       Total scale−0.16 (−0.80 to +0.48)P = .59r = 0.73
       Sensation scale+0.04 (−0.30 to +0.38)P = .84r = 0.73
       Pain scale−0.20 (−0.57 to +0.17)P = .42r = 0.55
       Movement scale+0.00 (−0.22 to +0.22)P = .94r = 0.60
      EuraHS-QoL
       Total scale+0.01 (−0.58 to +0.61)P = .58r = 0.73
       Pain scale+0.00 (−0.34 to +0.34)P = .58r = 0.72
       Restriction scale−0.04 (−0.39 to + 0.32)P = .63r = 0.73
       Cosmetic scale+ 0.05 (−0.13 to + 0.23)P = .74r = 0.74
      Convergent validity
      Spearman correlation coefficients
      3 weeks3 months12 months
      CCS
       CCS pain and VAS pain scaler = 0.60r = 0.70r = 0.62
       CCS pain and VRS scaler = 0.61r = 0.74r = 0.75
      EuraHS-QoL
       EuraHS-QoL pain scale and CCS pain scaler = 0.81r = 0.69r = 0.86
       EuraHS-QoL pain scale and VAS pain scaler = 0.48r = 0.66r = 0.64
       EuraHS-QoL pain scale and VRS scaler = 0.52r = 0.75r = 0.79
       EuraHS-QoL restriction scale and CCS movement scaler = 0.79r = 0.76r = 0.65
      CI, Confidence interval.
      Modified CCS (omitting the Sensation scale).
      According to the Wilcoxon signed rank test.
      Both the EuraHS-QoL and the CCS result in a Cronbach's α ≥ .90 for their different scales or domains at most of the measured time points, illustrating an excellent to good internal consistency for both hernia-specific QoL scores.
      The test-retest reliability measurement for the EuraHS-QoL score between 12 and 13 months demonstrates a good correlation with a Spearman correlation coefficient for all domains and for the overall score of r ≥ 0.72.
      We measured the convergent validity of the different pain measurements: EuraHS-QoL pain scale, CCS pain scale, VAS, and the VRS. The resulting Spearman correlation coefficients for the EuraHS-QoL pain scale at 3 months and 12 months were between, r = 0.64 and 0.86, showing a good correlation with the CCS pain scale, the VAS for pain, and the VRS.
      For the measurements at 3 weeks, the correlation for the EuraHS-QoL pain scale was less with the VAS for pain (r = 0.48) and with the VRS (r = 0.52), but it was good with the CCS pain scale (r = 0.81). The associations of the EuraHS-QoL pain scale with the CCS pain scale and the VAS for pain, and the EuraHS-QoL restriction scale with the CCS movement scale at 12 months are graphically shown in Fig 4.
      Figure thumbnail gr4
      Fig 4Graphical presentation of the correlations of the EuraHS-QoL pain scale with the CCS pain scale and the VAS for pain and the EuraHS-QoL restriction scale with the CCS movement scale at 12 months from a prospective validation study for the EuraHS-QoL score in 101 patients undergoing unilateral laparoscopic groin hernia repair.

      Other analyses

      We made an additional analysis comparing the EuraHS-QoL, the CCS, and the VAS for pain between the patients that were operated on with TEP versus TAPP. No significant differences were found between the 2 techniques.

      Discussion

      Key results

      Our evaluation of the EuraHS-QoL score in laparoscopic inguinal hernia repair showed a good internal consistency (Cronbach's α ≥ .90), a good test-rest reliability (Spearman correlation coefficient; r ≥ 0.72), and high correlation to detect chronic pain with the VAS for pain, the VRS, the CCS pain scale (Spearman correlation coefficient; r ≥ 0.64 and r ≤ 0.86), and for restriction of activity with the CCS movement scale (Spearman correlation coefficient; r ≥ 0.65 and r ≤ 0.79).
      A significant improvement of the QoL 3 weeks after elective laparoscopic inguinal hernia repair was seen compared with the preoperative assessment, with further improvement up to 12 months (P values < .05). No late complications or recurrences were recorded. Operations can be performed in ambulatory setting (>75%) or with a <24-hour admission (>95%) in the majority of the patients.

      Limitations

      The patients included in the study presented with uncomplicated unilateral inguinal hernias treated by laparoscopy with a self-fixating mesh. By excluding more complicated groin hernias or other methods of repair, a more homogeneous study cohort was formed. But in this group, a more favorable QoL outcome postoperatively can be expected than for the overall groin hernia repair population. This is illustrated by the high number of patients reporting no pain or zero values in the assessments, which limited the data available for performing the statistical validation tests.

      Interpretation

      The outcome after groin hernia repair is most often measured by the number of recurrences, which only allows for a dichotomic (Yes or No) measurement. This is insufficient to allow for an accurate description of what the patients perceive as a successful treatment. Sometimes the “cure” is perceived as being worse than the “disease,” eg, when the operation induces chronic pain and restricts activities in a patient with an asymptomatic or oligosymptomatic groin hernia. When measuring the outcome as the number of patients with chronic pain (lasting >3 months), we can use a categorical outcome variable, like the VRS (no pain–mild–moderate–severe pain), or a numeric variable, like the VAS, for pain.
      • Cunningham J.
      • Temple W.J.
      • Mitchell P.
      • Nixon J.A.
      • Preshaw R.M.
      • Hagen N.A.
      Cooperative hernia study. Pain in the post-repair patient.
      • Loos M.J.
      • Houterman S.
      • Scheltinga M.R.
      • Roumen R.M.
      Evaluating postherniorrhaphy groin pain: Visual Analogue or Verbal Rating Scale?.
      This allows for a quantification of the severity and the number of patients suffering chronic pain.
      Postoperative pain is probably the most relevant but not the only determinant of postoperative QoL. There is an increasing interest in assessing the quality of treatment by evaluating the QoL with PROMs.
      • Gabriel S.E.
      • Normand S.T.
      Getting the methods right—The foundation of patient-centered outcomes research.
      • Muysoms F.E.
      • Deerenberg E.B.
      • Peeters E.
      • Agresta F.
      • Berrevoet F.
      • Campanelli G.
      • et al.
      Recommendations for reporting outcome results in abdominal wall repair.
      • Ujiki M.B.
      • Gitelis M.E.
      • Carbray J.
      • Lapin B.
      • Linn J.
      • Haggerty S.
      • et al.
      Patient-centered outcomes following laparoscopic inguinal hernia repair.
      • Heniford B.T.
      • Walters A.L.
      • Lincourt A.E.
      • Novitsky Y.W.
      • Hope W.W.
      • Kercher K.W.
      Comparison of generic versus specific quality-of-life scales for mesh hernia repairs.
      • Belyansky I.
      • Tsirline V.B.
      • Klima D.A.
      • Walters A.L.
      • Lincourt A.E.
      • Heniford T.B.
      Prospective, comparative study of postoperative quality of life in TEP, TAPP, and modified Lichtenstein repairs.
      • Fränneby U.
      • Gunnarsson U.
      • Andersson M.
      • Heuman R.
      • Nordin P.
      • Nyrén O.
      • et al.
      Validation of an inguinal pain questionnaire for assessment of chronic pain after groin hernia repair.
      • Clay L.
      • Fränneby U.
      • Sandblom G.
      • Gunnarsson U.
      • Strigård K.
      Validation of a questionnaire for the assessment of pain following ventral hernia repair: The VHPQ.
      • Muysoms F.
      • Campanelli G.
      • Champault G.G.
      • DeBeaux A.C.
      • Dietz A.
      • Jeekel J.
      • et al.
      EuraHS: The development of an international online platform for registration and outcome measurement of ventral abdominal wall hernia repair.
      Ideally, PROMs should also include questions about restriction of activities by pain or discomfort in the operated groin, esthetical discomfort, testicular pain, sexual dysfunction, patient anxiety, and patient satisfaction. On the other hand, a good QoL questionnaire should be short and precise, thus a selection of what is considered most relevant has to be made.
      The CCS is a validated questionnaire for QoL assessment after repair of abdominal wall hernias. Of the 23 questions, 8 questions concern whether or not the patient feels the mesh. In our opinion, whether or not the patient feels the mesh is less relevant than if they feel pain and are restricted in their activity. Moreover, this high focus on mesh sensation makes the CCS appropriate only in the postoperative setting.
      We think a preoperative assessment is equally important to evaluate the effect of our treatment. Because the EuraHS working group wanted to provide a QoL assessment in their online database free of charge, we could not use the CCS in our platform. Our goal was to develop a short questionnaire, and we opted to include an esthetical item in our questions. We also wanted to construct our questionnaire to be applicable for groin and ventral hernias.
      The EuraHS-QoL score selected 9 questions in 3 domains that seem most relevant for evaluating patient QoL after hernia repair.
      • Muysoms F.
      • Campanelli G.
      • Champault G.G.
      • DeBeaux A.C.
      • Dietz A.
      • Jeekel J.
      • et al.
      EuraHS: The development of an international online platform for registration and outcome measurement of ventral abdominal wall hernia repair.
      The questionnaire is constructed in consensus by a panel of expert abdominal wall surgeons from a working group of the European Hernia Society. It provides a unique score for both groin hernias and ventral hernias. It has been proven that the preoperative pain level in groin hernia patients is adversely related to the risk of postoperative chronic pain.
      • Aasvang E.K.
      • Gmaehle E.
      • Hansen J.B.
      • Gmaehle B.
      • Forman J.L.
      • Schwarz J.
      • et al.
      Predictive risk factors for persistent postherniotomy pain.
      Therefore, it is mandatory to provide the possibility for preoperative evaluation of the patients with a QoL score.
      The EuraHS-QoL includes a domain for esthetic discomfort pre- and postoperatively. Although we thought that this would have been mostly relevant for ventral and incisional hernias, our study showed the domain's applicability to groin hernias. This study shows the EuraHS-QoL to have an excellent internal consistency, a good test-retest reliability, and convergent validity with the other evaluated pain or QoL assessments. After this validation for groin hernia patients, a validation study with the EuraHS-QoL score in a prospective, multicenter cohort of ventral hernia patients will be performed.
      We recommend avoiding penetrating fixation of meshes during laparoscopic groin hernia repair, as nonfixation or fixation with glue is equally effective and reduces the risk of postoperative pain.
      • Antoniou S.A.
      • Köhler G.
      • Antoniou G.A.
      • Muysoms F.E.
      • Pointner R.
      • Granderath F.A.
      Meta-analysis of randomized trials comparing nonpenetrating vs mechanical mesh fixation in laparoscopic inguinal hernia repair.
      • Poelman M.M.
      • van den Heuvel B.
      • Deelder J.D.
      • Abis G.S.
      • Beudeker N.
      • Bittner R.R.
      • et al.
      EAES Consensus Development Conference on endoscopic repair of groin hernias.
      Self-gripping meshes using ProGrip have been tested in large, high-quality studies on open anterior groin hernia repair.
      • Sanders D.L.
      • Nienhuijs S.
      • Ziprin P.
      • Miserez M.
      • Gingell-Littlejohn M.
      • Smeds S.
      Randomized clinical trial comparing self-gripping mesh with suture fixation of lightweight polypropylene mesh in open inguinal hernia repair.
      • Rönkä K.
      • Vironen J.
      • Kössi J.
      • Hulmi T.
      • Silvasti S.
      • Hakala T.
      • et al.
      Randomized multicenter trial comparing glue fixation, self-gripping mesh, and suture fixation of mesh in Lichtenstein hernia repair (FinnMesh Study).
      Birk et al
      • Birk D.
      • Hess S.
      • Garcia-Pardo C.
      Low recurrence rate and low chronic pain associated with inguinal hernia repair by laparoscopic placement of Parietex ProGrip™ mesh: Clinical outcomes of 220 hernias with mean follow-up at 23 months.
      were the first to publish on the safety and feasibility of the use of ProGrip in a laparoscopic TAPP approach with favorable outcome. Recently, Breshnahan et al
      • Bresnahan E.
      • Bates A.
      • Wu A.
      • Reiner M.
      • Jacob B.
      The use of self-gripping (Progrip™) mesh during laparoscopic total extraperitoneal (TEP) inguinal hernia repair: A prospective feasibility and long-term outcomes study.
      confirmed this for laparoscopic TEP repairs. To facilitate the intraoperative handling of the self-fixating mesh, a specific laparoscopic, self-fixating mesh was designed (ProGrip laparoscopic self-fixating mesh). To our knowledge, this report is the first description of its clinical use and performance. The results are favorable in terms of QoL assessment and safety.

      Generalizability

      The EuraHS-QoL score was validated for patients before and after inguinal hernia repair. Although the study included only laparoscopic repairs, we propose to accept the EuraHS-QoL as a valid tool for all types of groin hernia repair. Whether the EuraHS-QoL is also a valid tool to use in ventral or incisional hernia patients needs further investigation.
      In conclusion, the EuraHS-QoL score is a short and valid PROM for patients after groin hernia repair. Laparoscopic groin hernia repair with ProGrip laparoscopic, self-fixating mesh results in a favorable outcome and significant improvement of QoL compared with the preoperative assessment.
      This manuscript was written in accordance with the STROBE statement: Strengthening the reporting of observational studies in epidemiology.
      • von Elm E.
      • Altman D.G.
      • Egger M.
      • Pocock S.J.
      • Gotzsche P.C.
      • Vandenbroucke J.P.
      • et al.
      Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement: Guidelines for reporting observational studies.

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