Is the association found between faecaliths and right iliac fossa pain reliable?

The article on appendiceal faecaliths by Grimes et al. has proposed a very interesting finding; however, a few points need to be discussed before acceptance of the conclusion from this study. The selection of the cases and controls is merely on the basis of presence or absence of appendiceal faecaliths but the comparability of the groups with regards to age, gender and other demographic details has not been mentioned. This makes the control selection doubtful.

A better way of ascertaining the pre-operative and postoperative pain and other symptoms in this case would have been medical records. This would have addressed recall bias introduced through telephone interview and would have made the two groups comparable. The authors have not mentioned anything about the responders of the questionnaires. A few patients might have been too young to remember anything at all introducing limitation to recall. Were surrogate responders used to address this issue?

Many potential confounders were not addressed, for example, is there another cause of right iliac fossa pain in normal appendix? Mesenteric adenitis in children¹ has not been addressed in this patient population. Evaluation of the operative notes and detailed histological reports would have provided information about other potential causes.

The sample size is too small and such a finding could merely result from chance rather than having a clinical implication. Moreover, measure of association in a case control study is done by computing the odds ratio.² Most of the referenced studies in the discussion are of the paediatric age group again creating bias about the comparison; moreover, these referenced studies had a small sample size making acceptance of their results difficult. Unconditional logistic regression would have been a better model to look for association between right iliac fossa pain and faecaliths which will adjust for confounders.

The conclusion by the authors that removing normal-looking appendices would reduce re-admission cannot be accepted because of the lack of proper evidence which can only be obtained by a randomised controlled trial.