Costs & outcomes of hospitalized scrub typhus infection in a tertiary hospital in south India

Background & objectives: Scrub typhus is a rickettsial infection seen along the Asian-Pacific rim and imposes a considerable burden on affected people in low- and middle-income countries. The present study was aimed to determine the direct cost of hospitalization of scrub typhus and its trend over six years. Methods: This was a retrospective, observational, hospital based study of individuals admitted to the hospital, diagnosed with scrub typhus over six years, from January 2013 to December 2018. The potential out of pocket expenditure was evaluated. Results: A total of 198 patients were included in the study. The median cost of admission (adjusted to INR 2020) for the six years (2013 to 2018) was found to be ? 37,026 (US $ 490) [interquartile range (IQR) 22,996-64,992]. The median cost for patients admitted to the intensive care unit (ICU) was ? 128,046 (US $ 1695) (IQR 71,575-201,171), while the cost for patients admitted to the ward-alone was ? 33,232 (US $ 440) (IQR 19,609-45,373). The multivariable analysis showed that ARDS and SOFA score were the independent predictors of ICU admission. Interpretation & conclusions: Hospitalisation for scrub typhus is associated with a substantial healthcare expense. The predictors of increased cost were the presence of acute respiratory distress syndrome (ARDS), shock, increasing sequential organ failure assessment (SOFA) score and duration of hospital stay

INTERPRETATION AND ESTIMATION OF CONDITIONAL POWER IN INTERIM ANALYSES OF CLINICAL TRIALS: OFTEN IGNORED IN DECISION MAKING PROCESS

In group sequential trials, the interim results are more promising in the early termination of a trial either for efficacy or futility of the trial. This reduces the cost and time implications. Moreover, interim analyses play a key role to tackle the problem that arises due to adverse effects. In concern with the early stopping of trials, there are numerous stopping methods among them the Conditional power (CP) approach is best recommended. The CP approach provides the probability of getting significant results at the end of the study given the data observed so far. There are very few Indian studies that had incorporated the concept of CP and made decisions based on the results. This study popularises the CP approach detailing computing and its interpretation and is thereby facilitating clinical researchers to use this approach effectively. We have used real-time and hypothetical examples and illustrated the concept of CP under trend, CP under null, and CP under design. We suggest stopping the study for efficacy when the CP under null is greater than 80% and stopping the study for futility when CP under trend is less than 30%.