A comment on Incidence of occupational exposures in a tertiary health care center.

Sir,

This is in reference to the article entitled “Incidence of occupational exposures in a tertiary health care center” published in Indian J Sex Transm Dis 2012; 33:91-7.[1] The incidence of NSI is considerably higher than current estimates, due to gross under-reporting (often less than 50%).[23] In USA 600,000,000 receive NSI from conventional needles and sharps every year, while in UK, it is 1,00,000 health care workers/year.[4] In India, authentic data on NSI are scarce.[5] In that way, this study is an earnest effort for which the authors should be congratulated.

However, this study has a basic flaw. This study does not and cannot provide us with the incidence of occupational exposures as claimed by the authors. The methodology adopted for this study will yield prevalence and not incidence as the study is cross-sectional nature (as pointed out by the authors in methods section).[1] For arriving at incidence, a longitudinal study involving a follow-up of a cohort recruited at the beginning of the study should have been chosen. This cohort could be medical, paramedical or nursing staff.

If you have a look at the results, the point will become clearer. The results have been expressed as percentages (usual in prevalence study) as opposed to per thousand or per hundred per year (rate or incidence). This study actually provides us with a profile of needle stick injury in a tertiary health care center, and that is how it should have been titled.