RESUMEN
BACKGROUND: The Nurse Work Instability Scale (Nurse-WIS) is an occupation-specific instrument that ascertains "work instability," the interval before restricted work ability or prolonged sick leave occurs. The objective of the study was to assess if nurses with a high risk baseline-score in the Nurse-WIS take longer periods of sick leave due to musculoskeletal diseases and/or psychological impairments than other nurses. METHODS: A total of 4500 nurses randomly selected from one of the largest health insurance funds in Germany (DAK-Gesundheit) were invited by letter to participate in the study. The participants answered a questionnaire at baseline and gave consent to a transfer of data concerning sick leave during the twelve months following completion of the questionnaire from the health insurance to the study centre. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) for long-term sick leave were calculated. In order to analyze the association between the Nurse-WIS and sick leave during follow-up, a multiple ordinal logistic model (proportional odds model) was applied. RESULTS: A total of 1592 nurses took part in the study (response 35.6%). No loss of follow-up occurred. The number of nurses with a high score (20-28 points) in the Nurse-WIS was 628 (39.4%), and 639 (40.1%) had taken sick leave due to musculoskeletal diseases or psychological impairment during the follow-up period. The odds ratio for sick leave in nurses with a high Nurse-WIS score was 3.42 (95%CI 2.54-4.60). Sensitivity for long-term sick leave (< 42 days) was 64.1%, specificity 63.4%, PPV 17.0% and NPP 93.8%. CONCLUSION: The German version of the Nurse-WIS predicts long-term sick leave, but the PPV is rather low. Combining questionnaire data with secondary data from a health insurer was feasible. Therefore further studies employing this combination of data are advisable.
RESUMEN
BACKGROUND: Until now there has been a lack of effective screening instruments for health care workers at risk. To counteract the forecast shortage for health care workers, the offer of early interventions to maintain their work ability will become a central concern. The Nurse-Work Instability Scale (Nurse-WIS) seems to be suitable as a screening instrument and therefore a prospective study of a cohort of nursing staff from nursing homes was undertaken to validate the Nurse-Work Instability Scale (Nurse-WIS). METHODS: The follow-up data was used to test the sensitivity, specificity and the predictive values of the Nurse-WIS. The participants answered a questionnaire in the baseline investigation (T1) and in a follow-up 12 month after baseline. The hypothesis was that geriatric care workers with an increased risk according to the Nurse-WIS in T1 would be more likely to have taken long-term sick leave or drawn a pension for reduced work capacity in T2. RESULTS: 396 persons took part in T1 (21.3% response), 225 in T2 (42.3% loss-to-follow-up). In T1, 28.4% indicated an increased risk according to the Nurse-WIS. In T2, 10.2% had taken long-term sick leave or had drawn a pension for reduced work capacity. The sensitivity is 73.9% (95%-CI 55.7%-92.3%), the specificity is 76.7% (95%-CI 71.2%-82.8%). The ROC AUC indicated a moderate precision for the scale, at 0.74 (95%-CI 0.64-0.84). The PPV of the Nurse-WIS is 26.6%, and the NPV is 96.3%. For those with an increased risk according to the Nurse-WIS, the probability in T2 of long-term sick leave or a pension for reduced work capacity is around eight times higher (OR 8.3, 95%-CI 2.90-23.07). Persons who had indicated a long-term sick leave or made an application for a pension for reduced work capacity in T1 had a 17 times higher risk (OR 17.4, 95%-CI 3.34-90.55). CONCLUSION: The German version of the Nurse-WIS appears to be a valid instrument with satisfactory predictive capabilities for recording an impending long-term sick leave. Whether the Nurse-WIS can be used as a screening tool which helps to design risk adjusted prevention programs for the afflicted nurse should be studied.