Loss to Follow-up: A Deceptive Enigma

Abstract Loss to follow-up indicates both patients not reporting and inability to trace them during the required follow-up period or study period. Significant loss to follow-up can affect the validity of a study and thereby the impact of that study. The importance of loss to follow-up has been very scarcely and meagerly highlighted in literature. More than one-fifth loss to follow-up can lead to significant selection bias. Loss to follow-up affects delivery of appropriate patient care. In the cohort studies, follow-up rates of 50 to 80% are accepted by authors, due to lack of any recommendations. The causes of loss to follow-up may vary from patient’s age, occupation, chronicity of the disease, etc. Loss to follow-up needs to be reported in all prospective studies, and intention to treat analysis should be applied. This will improve the validity of study, provide reliable results, and reflect the true effect of the intervention used in the study. It also helps to determine the actual survival rates in fatal diseases. The course of a disease can also be monitored, and appropriate intervention can be done at an appropriate point of time to prevent morbidity and mortality. Its overall benefits are better patient care and improved outcomes of the treatment method.