Interest has increased in using health status measures in clinical practice for individual-patient applications. The authors propose six measurement standards for such use: practical features, breadth of health measured, depth of health measured, precision for cross-sectional assessment, precision for longitudinal monitoring, and validity. They evaluated five health status surveys: Functional Status Questionnaire (FSQ), Dartmouth COOP Poster Charts (COOP), Nottingham Health Profile (NHP), Duke Health Profile (DUKE), and SF-36 Health Survey (SF-36). These surveys were assessed based on the six standards. The most problematic feature was their lack of precision for individual-patient applications. Across all scales, reliability standards for individual assessment and monitoring were not satisfied, and 95% confidence intervals were very wide. There was little evidence of the validity of the five surveys for screening, diagnosing, or monitoring individual patients. The health status surveys examined may not be suitable for monitoring individual patients. Clinical usefulness of existing measures might be demonstrated as clinical experience is broadened. At this time, new instruments or adaptations of existing measures and scaling methods are needed for individual-patient assessment and monitoring. Health status measures have been used in group-level applications for over 25 years, including health profiles, treatment evaluations, health outcomes comparisons, health policy assessments, and general population health. Recently, there has been growing interest in using these measures in clinical practice for individual-patient assessment and treatment monitoring. This interest is due to the limitations of the current medical paradigm, poor correspondence between physician and patient ratings of functional status, emotional well-being, and quality of life, and the increasing prevalence of chronic disease. Numerous position papers have proposed measurement standards for group-level applications. This paper proposes standards for individual-patient applications and evaluates five general health status surveys proposed for use in clinical practice. The goal is to stimulate critical appraisal of existing measures and encourage new measurement development. The surveys evaluated were designed for group-level applications but have also been recommended for use in clinical practice. The authors conclude that the five surveys may not be suitable for individual-patient monitoring and that new instruments or adaptations are needed.Interest has increased in using health status measures in clinical practice for individual-patient applications. The authors propose six measurement standards for such use: practical features, breadth of health measured, depth of health measured, precision for cross-sectional assessment, precision for longitudinal monitoring, and validity. They evaluated five health status surveys: Functional Status Questionnaire (FSQ), Dartmouth COOP Poster Charts (COOP), Nottingham Health Profile (NHP), Duke Health Profile (DUKE), and SF-36 Health Survey (SF-36). These surveys were assessed based on the six standards. The most problematic feature was their lack of precision for individual-patient applications. Across all scales, reliability standards for individual assessment and monitoring were not satisfied, and 95% confidence intervals were very wide. There was little evidence of the validity of the five surveys for screening, diagnosing, or monitoring individual patients. The health status surveys examined may not be suitable for monitoring individual patients. Clinical usefulness of existing measures might be demonstrated as clinical experience is broadened. At this time, new instruments or adaptations of existing measures and scaling methods are needed for individual-patient assessment and monitoring. Health status measures have been used in group-level applications for over 25 years, including health profiles, treatment evaluations, health outcomes comparisons, health policy assessments, and general population health. Recently, there has been growing interest in using these measures in clinical practice for individual-patient assessment and treatment monitoring. This interest is due to the limitations of the current medical paradigm, poor correspondence between physician and patient ratings of functional status, emotional well-being, and quality of life, and the increasing prevalence of chronic disease. Numerous position papers have proposed measurement standards for group-level applications. This paper proposes standards for individual-patient applications and evaluates five general health status surveys proposed for use in clinical practice. The goal is to stimulate critical appraisal of existing measures and encourage new measurement development. The surveys evaluated were designed for group-level applications but have also been recommended for use in clinical practice. The authors conclude that the five surveys may not be suitable for individual-patient monitoring and that new instruments or adaptations are needed.