Comparison of Frail Patients Versus Nonfrail Patients ≥65 Years of Age Undergoing Percutaneous Coronary Intervention

A new method of classifying prognostic comorbidity in longitudinal studies: Development and validation

Mary E. Charlson, Peter Pompei, Kathy L. Aleš et al. · Journal of Chronic Diseases · 1987 · 48.8K citations

Prognostic Assessment, Longitudinal Studies, Prognostic Comorbidity +11

Frailty in Older Adults: Evidence for a Phenotype

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Lower Extremity Function and Subsequent Disability: Consistency Across Studies, Predictive Models, and Value of Gait Speed Alone Compared With the Short Physical Performance Battery

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Multiple Imputation for Nonresponse in Surveys.

Peter Lynn, Donald B. Rubin · Journal of the Royal Statistical Society Series D (The Statistician) · 1988 · 2.3K citations

Reliability, Survey (Human Research), Engineering +4

Short form 36 (SF36) health survey questionnaire: normative data for adults of working age.

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