Reading a research paper: The relevance of "ecological validity".

Sir,

The approach by Andrade[1] is indeed creditable, and pertinent issues on reading a research paper are highlighted and discussed. However, there are some aspects, which though discussed, tend not to fully reflect the “between the line” issues.

The most important issue that springs to mind is related to the “ecological validity.” The study by Malm et al.[2] was conducted in Finland, and an in-depth understanding and clinical-cum-research application is possible only with at least some (if not in-depth) understanding of the organization, governance, and delivery of mental health care in Finland. To exemplify this assertion, the prescription, dispensing, and adherence to psychotropics is different across different countries and tends to be influenced by a variety of socio-cultural and pharmaco-economic factors.[3]

Though ecological validity has been partly discussed,[1] it is probably the most relevant and key factor in the interpretation and application of evidence-based medicine (read “medicine” as “psychiatry”), and hence merits further discussion.

Andrade[1] has argued the case of “apples” versus “oranges” (confounding by indication), but it will be relevant to keep in perspective that the non-SSRI exposure group may actually have contained depressed patients who did not receive/want these medications. Possibly, these females may have been referred for only therapy (e.g. NICE guidance in UK advocates only psychological therapy for “mild depression”)[4] or may have been prescribed non-SSRI antidepressants, or suffered from additional/co-morbid psychological problems (e.g. depression with prominent anxiety symptoms which would have led onto triage toward psychological treatments rather than pharmacological treatment).

The same could be argued on the point raised by Andrade that “depression was likely responsible for both SSRI prescription and alcohol use.” In the west, as per guidance-based management of depression,[4] it is generally advisable not to prescribe antidepressants for people who are drinking alcohol and suffering with co-morbid depression. Additionally, there is a high co-morbidity between depression and alcohol use, and it is clinically not easy to tease out the cause and effect relationship. Lastly, there are differences in terms of the psychological and material support received by women in India compared to those in the west; but that may be more qualitative and resource related than being quantitatively inferior (as postulated[1] ). Hence, Andrade's assertion that “…underlying psychiatric condition (depression) was likely responsible for both SSRI prescription and alcohol use…” does not capture the full essence of the possible scenarios that would affect the interpretation of the results.

Amongst other factors, burgeoning and easy accessibility to literature, along with rapid information sharing, has led to the scientific world becoming a smaller place to be in. Hence, ecological and cultural issues should be given more credence as they contribute significantly not only to the skill and art of “reading between and beyond the lines…,”[1] but also to the clinical application, generalizability, and relevance of such research findings.