INguinal hernia: operative or Conservative Approach (INCA TRIAL)?

The presence of an inguinal hernia is an indication for an elective herniorraphy if no contra-indications are present. However, life expectancy is equal for surgical and observational management. Additionally, recent studies indicate that there is a high incidence of chronic postoperative pain after inguinal hernia surgery.

The primary objective of this multicentre study is to investigate whether abstaining from operation is a better alternative to surgical treatment in male inguinal hernia patients. The target sample of 800 men will be randomly assigned to either surgical or observational non-surgical management. The outcomes of the study are pain/discomfort, quality of life, event-free survival and costs.

To determine whether there is any difference in the mean of pain/discomfort scores (4 point scale, 0-3) during follow-up with 0,15 points and a power of 80%, the required sample size in each group is 400 patients. With the help of a Student's t-test a non-inferiority hypothesis will be tested. The hypothesis states that both groups have had the same mean pain/discomfort scores.

The secondary objective is to investigate whether a non-surgical approach is cost-effective compared to current practice (hernia operation). The third objective is a comparison of the event-free survivorship functions of both groups. The fourth objective is an evaluation of the baseline risk factors in the not-operated group with respect to their ability to predict which type of patients will require surgery during the follow-up period.

Non-inferiority hypothesis: observation is not inferior to operation with respect to the mean of pain and discomfort during 3 years follow-up.

N/A

Operative correction of the inguinal hernia or observative management.