Study design and data
The intervention “HALTgeben” (“Higher Patient Satisfaction through Fair Working Conditions in Healthcare”) was conducted among healthcare workers in 11 German health services institutions, namely, seven general and three specialised hospitals and one elderly care centre. The intervention was motivated by the personnel management of these health services institutions following the invitation to participate in the study. These institutions were selected because they are located near the consultants’ offices and have a sufficient number of workers and patients required to assess the effects of the intervention on the main intervention outcomes. The main aim of the intervention was to improve the self-assessed physical and mental work ability of healthcare workers by modifying the working conditions in the intervention wards. The intervention was conducted in a two-arm, cluster-randomised design whose study protocol and baseline results have already been published elsewhere [The survey data used in the present study was collected in the intervention and control arms at baseline (T0) and two follow-up times (T1 and T2) between June to December 2019, September to December 2020 and August to October 2021, respectively. Healthcare workers who gave informed consent to participate in the surveys were able to fill the questionnaires either online or on paper. All workers in the intervention wards were given the chance to participate in the workshops delivered in the intervention (see below). However, not all workers in the single intervention wards took part in the surveys. Outcomes were measured by appropriate validated psychometric instruments comprising physical and psychosocial working conditions, work ability, and perceived physical and mental health (see [age and sex.The physical and mental work ability as measured with two items of the Work Ability Index Questionnaire “How would you appraise your current work ability in relation to the physical work demands?” and “How would you appraise your current work ability in relation to the mental work demands?”, respectively, with answer format ranging from 1 to 5 as follows: 1: poor, 2: not good, 3. good, 4: very good and 5: excellent [The scales of the ERI Questionnaire effort (6 items), reward (11 items) and overcommitment (6 items), with answer format: 1: strongly disagree, 2: disagree, 3: agree and 4: strongly agree [In addition, information on ward transfers was collected at the T1 and T2 follow-ups since these could have resulted in confounding effects, especially due to the disruptions in the healthcare system during the first year of the COVID-19 pandemic in 2020.