Patient rating of wrist pain and disability: a reliable and valid measurement tool.

OBJECTIVE: The goal of this study was to develop a reliable and valid tool for quantifying patient-rated wrist pain and disability. DESIGN: Survey, tool development, reliability, and validity study. SETTING: Upper extremity unit. PARTICIPANTS: One hundred members of the International Wrist Investigators were surveyed by mail to assist in development of the scale. Patients with distal radius (n = 64) or scaphoid (n = 35) fractures were enrolled in a reliability study, and 101 patients with distal radius fractures were enrolled in a validity study. INTERVENTION: Information from the expert survey, biomechanical literature, and patient interviews was used as a basis for item generation and definition of structural limitations for a scale that would be practical in the clinic. Patients with distal radius or scaphoid fractures completed the Patient-Rated Wrist Evaluation (PRWE) on two occasions to determine test-retest reliability. Patients with distal radius fractures (n = 101) completed the PRWE and the SF-36 and were tested with traditional impairment measures at baseline and at two, three, and six months after fracture to determine construct and criterion validity. MAIN OUTCOME MEASURES: Reliability coefficients (ICCs) and validity correlations (Pearson product moment correlations). RESULTS: Patient opinions on pain and on ability to do activities of daily living and work were thought to be the most important dimensions to include in subjective outcome tools. Brevity and simplicity were seen as essential in the clinic environment. A fifteen-item questionnaire (the PRWE) was designed to measure wrist pain and disability. Test-retest reliability was excellent (ICCs > 0.90). Validity assessment demonstrated that the instrument detected significant differences over time (p < 0.01) and was appropriately correlated with alternate forms of assessing parameters of pain and disability. CONCLUSIONS: The PRWE provides a brief, reliable, and valid measure of patient-rated pain and disability.

Persistently low natural killer cell activity, age, and environmental stress as predictors of infectious morbidity.

In recent studies of 'low natural killer (NK) cell syndrome', low NK activity was measured in individuals who were symptomatic, and therefore a causal relationship between low NK activity and infectious or other disease manifestations could not be concluded. However, preliminary work by members of our collaborative team (S.L. and R.H.) provided some indications for chronic low NK activity preceding and predicting subsequent infectious morbidity. This present study was designed to address this causal question in a larger sample, using a longitudinal design. Subjects were 106 healthy normal volunteers from the community. They were examined medically and psychosocially at baseline, and were then followed over a 6-month interval, with serial monthly assessments over the study period. The results supported our hypothesis that individuals who were currently healthy, but who exhibited a pattern of natural immunity characterized by persistently low NK cytotoxicity would be at risk for development of infectious sequelae over a 6-month follow-up period. The results also showed that younger age and the perception of more severe 'hassles' or stressors also predicted more infectious morbidity during the 6-month study period. Chronological age appeared to have both a direct, as well as indirect (via NK activity) association with illness outcome. Contrary to our expectation, the report of environmental stressors was directly associated with illness outcome, but not indirectly associated with outcome via natural immunity.

Persistently low natural killer cell activity in normal adults: immunological, hormonal and mood correlates.

This current study is concerned with the identification of the incidence of persistently low natural killer (NK) cell activity in an essentially healthy population of young adults, and the characterization of the psychological profile associated with this pattern of NK activity. Eighty-eight individuals, between the ages of 18 and 44 years, were accrued to this project. Subjects were tested serially, at baseline induction into the study, and at 2 and 4 weeks follow-up. Baseline assessment included a complete physical examination and laboratory work-up in order to exclude anyone ill at the time of enrollment, and to have complete physical status information on all subjects at the time of accrual. NK activity, urinary catecholamine levels and psychological status were also assessed at baseline, and at the specified follow-up intervals. Individuals with low NK activity were operationally defined as those having NK function either below the group mean, or below the group lowest quartile, at baseline and at two follow-up assessments. Results showed that in both univariate analyses, as well as in logistic regression models, age and the perception of environmental stressors or 'hassles' predicted persistently low NK activity. Younger subjects, who perceived environmental events to which they were exposed as more serious in nature, were more likely to exhibit a persistently low NK profile over time than older individuals who perceived daily events as less important to them.