An outcome measure to assess functional recovery after stroke that is easily obtainable and meaningful to the patient can be very useful for assessing risks and benefits of therapeutic strategies. Home-time, which is defined as the total number of days spent alive by the patient at home, outside healthcare institutions after discharge from an index stroke event, is an example of a patient-centered outcome measure that meets this need.1–3 The first known description of home-time as an outcome measure for stroke was noted in a study published in Stroke in 2008.4 In this study, home-time was demonstrated to be a robust and objective measure of poststroke recovery.
In 2013, the Patient-Centered Outcomes Research Institute provided funding for a study entitled “Patient-Centered Research into Outcomes Stroke Patient Prefer and Effectiveness Research” (PROSPER), which aimed to help patients, caregivers, and healthcare providers to make informed decisions regarding stroke care through comparative effectiveness research.3 Through qualitative work with patient partners, time spent at home after stroke was identified as a high-priority outcome.1 The home-time metric represents this value as an easy-to-understand concept, defined and measurable in terms relevant to patients and their caregivers.
Development and Definition
Home-time is calculated as total number of days alive and spent out of the hospital, inpatient rehabilitation, or a skilled nursing facility after the index hospital discharge. By convention, home-time is generally considered as the number of days at home during a single year; however, home-time may be calculated for other periods (eg, 30 or 90 days). Information about days spent outside the home can be obtained from administrative data sets (eg, Medicare), from healthcare resources (eg, electronic medical record), or from data collected as part of clinical trials. We evaluated home-time in patients after stroke using claims data and found that it could be reliably measured and provided an objective and reproducible outcome measure.5
Figure 1 provides an example of 1-year home-time calculation for a hypothetical poststroke patient. Mrs Bee was admitted to Best General Hospital for left middle cerebral artery ischemic stroke on May 15, 2017, and discharged on May 2, 2017. After her discharge, she was admitted to an inpatient rehabilitation facility for 10 days and then transitioned to home. During the following months, she experienced 1 hospital readmission that lasted for 5 days (August 5–10, 2017) with a diagnosis of pneumonia. After this readmission, she was discharged to a skilled nursing facility where she remained for 10 days (August 10–20, 2017) before returning to home. Mrs Bee remained alive and at home until May 15, 2018. One-year home-time is therefore calculated as 340 days.
Clinician-reported outcomes commonly used in clinical trials, such as the modified Rankin Scale (mRS), Barthel Index (BI), and the National Institutes of Health Stroke Scale, do not fully capture the postdischarge experience of stroke survivors. They also experience other important limitations such as poor interobserver variability (mRS),6 floor and ceiling effect (BI),7 and a focus on measuring physical impairment but not functional deficit (National Institutes of Health Stroke Scale).8 Home-time is a straightforward concept for nonclinical audiences, which facilitates dissemination of clinical research results.
Use of home-time as an outcome measure can also make it possible to conduct clinical trials in a timely and efficient manner. One frequently encountered problem in conducting clinical studies is patient attrition. When a patient is lost to follow-up, clinician-reported outcomes such as mRS or BI cannot be obtained. Availability of home-time from administrative data sets is an inexpensive, efficient, and timely tool to compare different treatments in real-world settings.5,9 Administrative data linkages allow home-time to be calculated in all patients, without requiring an in-person or telephone follow-up visit. Because home-time is strongly correlated with global disability as measured by mRS, it can be used as a surrogate for mRS when it is not obtainable because the patient is lost to follow-up.4,5,9 As it is calculated objectively, home-time is not influenced by the same interobserver variability that affects other measures of stroke recovery such as mRS.6 Unlike the mRS, which is an ordinal measure, the number of days spent at home is a continuous outcome measure (ratio data) that permits use of more powerful statistical techniques. The variable home-time has now been used in a number of epidemiologic and clinical outcomes analyses.4,9–13
One comparative effective analysis in the PROSPER study compared longitudinal outcomes for ischemic stroke patients with atrial fibrillation who were discharged on oral anticoagulant warfarin with patients not discharged on any oral anticoagulant during the period of 2 years using Medicare claims.12 Patients discharged on warfarin spent 47.6 more days at home compared with patients not prescribed any oral anticoagulant, thus showing the significant advantages of anticoagulation for secondary prevention of cardiovascular complications in this patient population. Another PROSPER study similarly confirmed advantage of prescribing statin for stroke survivors at discharge. On average, those who received statins at discharge spent 28 more days at home compared with those who did not.11 These findings highlight the ease of communication that use of home-time variable in research studies provides in conveying advantages of important therapies. A recent study that was conducted in Alberta, Canada, showed that, among patients with different stroke types, patients with intracerebral hemorrhage had the least home-time whereas patients with transient ischemic attack had the longest home-time. This study demonstrates feasibility of adoption and acceptance of home-time as an outcome measure beyond the United States.9
As with other stroke outcome measures, home-time is prone to some limitations. Two patients with similar number of days at home may have very different care requirements, which may not be easily estimated from available data. Variability in availability of postdischarge care and assistance may contribute to observed differences in home-time among patients covered by different insurance types, treated in different health systems, or from different countries in clinical studies. Statistical adjustment for social factors that may influence home-time (eg, marital status, income level) may not be feasible because such data elements are inconsistently collected in clinical research studies. Developing a more robust definition for home-time that can be used in the National Institutes of Health Common Data Elements would facilitate its use as an end point for clinical trials.14 Home-time may have less validity for patients who are disabled at baseline before their index stroke.
Home-time is defined most simply as the time a patient spends at home after an index event. The use of home-time as an outcome measure may help inform healthcare providers and patients in identifying more effective and patient-centered stroke treatments. We encourage the use of home-time by researchers, nurses, and other practitioners in clinical neuroscience who are in need of a generalizable concept to represent a high-priority, patient-centered outcome after stroke.
1. Hannah D, Lindholm B, Maisch L. Certain uncertainty: life after stroke
from the patient’s perspective. Circ Cardiovasc Qual Outcomes
2. O’Brien EC, Xian Y, Fonarow GC, Olson DM, Schwamm LH, Hernandez AF. Clinical commentary on "Certain uncertainty: life after stroke
from the patient’s perspective". Circ Cardiovasc Qual Outcomes
3. Xian Y, O’Brien EC, Fonarow GC, et al. Patient-Centered Research Into Outcomes Stroke
Patients Prefer and Effectiveness Research: implementing the patient-driven research paradigm to aid decision making in stroke
care. Am Heart J
4. Quinn TJ, Dawson J, Lees JS, et al. Time spent at home poststroke—"home-time" a meaningful and robust outcome
measure for stroke
5. Fonarow GC, Liang L, Thomas L, et al. Assessment of home-time after acute ischemic stroke
in Medicare beneficiaries. Stroke
6. Duncan PW, Jorgensen HS, Wade DT. Outcome
measures in acute stroke
trials—a systematic review and some recommendations to improve practice. Stroke
7. Dromerick AW, Edwards DF, Diringer MN. Sensitivity to changes in disability after stroke
: a comparison of four scales useful in clinical trials. J Rehabil Res Dev
8. Young FB, Weir CJ, Lees KR, GAIN International Trial Steering Committee and Investigators. Comparison of the National Institutes of Health Stroke
Scale with disability outcome
measures in acute stroke
9. Yu AYX, Rogers E, Wang M, et al. Population-based study of home-time by stroke
type and correlation with modified Rankin score. Neurology
10. Mishra NK, Shuaib A, Lyden P, et al. Home time is extended in patients with ischemic stroke
who receive thrombolytic therapy: a validation study of home time as an outcome
11. O’Brien EC, Greiner MA, Xian Y, et al. Clinical effectiveness of statin therapy after ischemic stroke
: primary results from the statin therapeutic area of the Patient-Centered Research Into Outcomes Stroke
Patients Prefer and Effectiveness Research (PROSPER) study. Circulation
12. Xian Y, Wu J, O’Brien EC, et al. Real world effectiveness of warfarin among ischemic stroke
patients with atrial fibrillation: observational analysis from Patient-Centered Research into Outcomes Stroke
Patients Prefer and Effectiveness Research (PROSPER) study. BMJ
13. O’Brien EC, Xian Y, Xu H, et al. Hospital variation in home-time after acute ischemic stroke
: insights from the PROSPER study (Patient-Centered Research Into Outcomes Stroke
Patients Prefer and Effectiveness Research). Stroke
14. Saver JL, Warach S, Janis S, et al. Standardizing the structure of stroke
clinical and epidemiologic research data: the National Institute of Neurological Disorders and Stroke
Common Data Element (CDE) project. Stroke