Simple questionnaire for assessing core outcomes in inguinal hernia repair.

BACKGROUND Patient-oriented questionnaires are indispensable in the assessment of surgical outcome. The psychometric properties of a brief multidimensional instrument were examined in patients with inguinal hernia undergoing surgery. METHODS Fifty-one patients (mean(s.d.) age 50·6(17·4) years; 48 men) participated. The following questionnaire properties were assessed for the Core Outcome Measures Index adapted for patients with hernia (COMI-hernia) and the EuroQol: practicability, floor and ceiling effects, test-retest reliability (over 2 weeks), construct validity (by comparison with other relevant scales) and responsiveness 9 months after surgery as standardized response mean (SRM). RESULTS The questionnaires were easy to implement and well accepted by the patients. Ceiling effects at baseline were 2 per cent for the COMI-hernia, 8 per cent for EuroQol-visual analogue scale (EQ-VAS) and 35 per cent for EuroQol-Five Dimensions (EQ-5D); no instrument showed floor effects. The reproducibility of individual COMI-hernia items was good, with test-retest differences within one grade ranging from 41 of 45 for 'social/work disability' to 44 of 45 for 'general quality of life'. The intraclass correlation coefficients were moderately high for COMI-hernia (0·74) and EQ-VAS (0·77), but low for EQ-5D (0·43). COMI-hernia scores correlated in the expected manner with related scales (r = 0·42-0·72, P < 0·050). COMI-hernia was the most responsive instrument (SRM 1·42). CONCLUSION The COMI-hernia and EQ-VAS general health scale represent reliable, valid and sensitive tools for assessing multidimensional outcome in patients with inguinal hernia undergoing surgical treatment.