Additional file 1 of The application of unsupervised deep learning in predictive models using electronic health records

Additional file 1: Figure S1. Examples of the multistage functions used in simulation studies. Figure S2. Examples of the continuous functions used in simulation studies in Appendix

Additional file 1 of The application of unsupervised deep learning in predictive models using electronic health records

Additional file 1: Figure S1. Examples of the multistage functions used in simulation studies. Figure S2. Examples of the continuous functions used in simulation studies in Appendix

Characteristics of patients in follow up visit and no follow up visit groups for logistic models (n = 30,702).

<p>Characteristics of patients in follow up visit and no follow up visit groups for logistic models (n = 30,702).</p

The association between outpatient follow-up visits and all-cause non-elective 30-day readmissions: A retrospective observational cohort study

<div><p>Background</p><p>As an effort to reduce hospital readmissions, early follow-up visits were recommended by the Society of Hospital Medicine. However, published literature on the effect of follow-up visits is limited with mixed conclusions. Our goal here is to fully explore the relationship between follow-up visits and the all-cause non-elective 30-day readmission rate (RR) after adjusting for confounders.</p><p>Methods and results</p><p>To conduct this retrospective observational study, we extracted data for 55,378 adult inpatients from Advocate Health Care, a large, multi-hospital system serving a diverse population in a major metropolitan area. These patients were discharged to Home or Home with Home Health services between June 1, 2013 and April 30, 2015. Our findings from time-dependent Cox proportional hazard models showed that follow-up visits were significantly associated with a reduced RR (adjusted hazard ratio: 0.86; 95% CI: 0.82–0.91), but in a complicated way because the interaction between follow-up visits and a readmission risk score was significant with p-value < 0.001. Our analysis using logistic models on an adjusted data set confirmed the above findings with the following additional results. First, time matter. Follow-up visits within 2 days were associated with the greatest reduction in RR (adjusted odds ratio: 0.72; 95% CI: 0.63–0.83). Visits beyond 2 days were also associated with a reduction in RR, but the strength of the effect decreased as the time between discharge and follow-up visit increased. Second, the strength of such association varied for patients with different readmission risk scores. Patients with a risk score of 0.113, high but not extremely high risk, had the greatest reduction in RR from follow-up visits. Patients with an extremely high risk score (> 0.334) saw no RR reduction from follow-up visits. Third, a patient was much more likely to have a 2-day follow-up visit if that visit was scheduled before the patient was discharged from the hospital (30% versus < 5%).</p><p>Conclusions</p><p>Follow-up visits are associated with a reduction in readmission risk. The timing of follow-up visits can be important: beyond two days, the earlier, the better. The effect of follow-up visits is more significant for patients with a high but not extremely high risk of readmission.</p></div

Characteristics of patients with and without follow-up visits for survival models (n = 55,378).

<p>Characteristics of patients with and without follow-up visits for survival models (n = 55,378).</p

Joint distribution of the actual and scheduled follow-up visits (n = 65,539).

<p>Joint distribution of the actual and scheduled follow-up visits (n = 65,539).</p

The effect of early follow-up visits on readmission risk for patients with different raw risk scores.

<p>The effect of early follow-up visits on readmission risk for patients with different raw risk scores.</p

Comparison of Readmission Rate (RR) for Patients with (YF) and without (NF) follow-up visits on or before various days.

<p>Comparison of Readmission Rate (RR) for Patients with (YF) and without (NF) follow-up visits on or before various days.</p

Estimated hazard ratio for a follow-up visit for patients with different risk scores.

<p>Estimated hazard ratio for a follow-up visit for patients with different risk scores.</p