Letter to the Editor

I read with great interest the article by McAlister and colleagues[1] on weekend versus weekday discharge outcomes.

The authors addressed length of stay (LOS) as a potential confounder in their inquiry. They ran regressions with and without LOS as a control and stated their results did not change; the findings imply LOS did not rest in the causal pathway between calendar day of discharge and outcomes.

I would like to highlight a recent article in which the authors found the reverse. Bartel et al.[2] applied a clever instrumental analysischoosing admission day (Sunday and Monday vs Tuesday through Saturday) as the instrumentto determine outcomes based on LOS. The investigators also ran a number of convincing falsification tests to verify their study design. They found an inverse association between greater length of hospital stay and readmissions and mortality.

Although Bartel et al. used a narrower spectrum of diagnoses and analyzed Medicare beneficiaries only, the results illuminate the difficulty in understanding the relationship between time in house and the day of discharge. If LOS influences mortality and readmission rates, overlooking its effect may obscure physician efforts to reduce LOS, for the laudatory goal of lessening return hospital trips and death.

The book on LOS impact remains open. We must remain uncertain of the interplay between days in house, mortality, readmission, and the weekend effect until further studies can elucidate how these variables interact.

I read with great interest the article by McAlister and colleagues[1] on weekend versus weekday discharge outcomes.

The authors addressed length of stay (LOS) as a potential confounder in their inquiry. They ran regressions with and without LOS as a control and stated their results did not change; the findings imply LOS did not rest in the causal pathway between calendar day of discharge and outcomes.

I would like to highlight a recent article in which the authors found the reverse. Bartel et al.[2] applied a clever instrumental analysischoosing admission day (Sunday and Monday vs Tuesday through Saturday) as the instrumentto determine outcomes based on LOS. The investigators also ran a number of convincing falsification tests to verify their study design. They found an inverse association between greater length of hospital stay and readmissions and mortality.

Although Bartel et al. used a narrower spectrum of diagnoses and analyzed Medicare beneficiaries only, the results illuminate the difficulty in understanding the relationship between time in house and the day of discharge. If LOS influences mortality and readmission rates, overlooking its effect may obscure physician efforts to reduce LOS, for the laudatory goal of lessening return hospital trips and death.

The book on LOS impact remains open. We must remain uncertain of the interplay between days in house, mortality, readmission, and the weekend effect until further studies can elucidate how these variables interact.

I read with great interest the article by McAlister and colleagues[1] on weekend versus weekday discharge outcomes.

The authors addressed length of stay (LOS) as a potential confounder in their inquiry. They ran regressions with and without LOS as a control and stated their results did not change; the findings imply LOS did not rest in the causal pathway between calendar day of discharge and outcomes.

I would like to highlight a recent article in which the authors found the reverse. Bartel et al.[2] applied a clever instrumental analysischoosing admission day (Sunday and Monday vs Tuesday through Saturday) as the instrumentto determine outcomes based on LOS. The investigators also ran a number of convincing falsification tests to verify their study design. They found an inverse association between greater length of hospital stay and readmissions and mortality.

Although Bartel et al. used a narrower spectrum of diagnoses and analyzed Medicare beneficiaries only, the results illuminate the difficulty in understanding the relationship between time in house and the day of discharge. If LOS influences mortality and readmission rates, overlooking its effect may obscure physician efforts to reduce LOS, for the laudatory goal of lessening return hospital trips and death.

The book on LOS impact remains open. We must remain uncertain of the interplay between days in house, mortality, readmission, and the weekend effect until further studies can elucidate how these variables interact.