Stress Management Among Nurses and Midwives in Inpatient Care

Work Overload is assessed using the corresponding subscale of the Trier Inventory for Chronic Stress (TICS). The TICS is a 57-item self-report questionnaire assessing chronic stress across nine domains. Items are rated on a 5-point frequency scale from 0 (never) to 4 (very often/always) with reference to experiences during the previous three months. Higher subscale scores indicate greater chronic stress in the respective domain.

Social Overload is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Pressure to Perform is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Work Discontent is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Excessive Demands at Work are assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Lack of Social Recognition is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Social Tensions are assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Social Isolation is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Chronic Worrying is assessed using the corresponding subscale of the TICS. Higher subscale scores indicate greater chronic stress in this domain.

Physical health-related quality of life is assessed using the Physical Component Summary (PCS-12) of the 12-Item Short Form Health Survey (SF-12). The SF-12 is a 12-item self-report measure of health-related quality of life. The PCS-12 is calculated according to the standardized SF-12 scoring algorithm, with higher scores indicating better physical health-related quality of life.

Mental health-related quality of life is assessed using the Mental Component Summary (MCS-12) of the 12-Item Short Form Health Survey (SF-12). The MCS-12 is calculated according to the standardized SF-12 scoring algorithm, with higher scores indicating better mental health-related quality of life.

Sleep quality is assessed using the global score of the Pittsburgh Sleep Quality Index (PSQI). The PSQI assesses sleep quality and sleep disturbances over the previous month across seven components. The seven component scores are summed to obtain a global score ranging from 0 to 21, with higher scores indicating poorer sleep quality.

Depressive symptoms are assessed using the German version (ADS, Allgemeine Depressionsskala) of the Center for Epidemiologic Studies Depression Scale (CES-D). The 20-item self-report questionnaire assesses the frequency of depressive symptoms during the previous week. Items are rated on a 4-point scale, resulting in a total score ranging from 0 to 60. Higher scores indicate greater depressive symptom severity.

Heart rate variability is assessed during a 10-minute resting measurement. The root mean square of successive differences (RMSSD) is calculated from successive normal-to-normal (NN) interbeat intervals and is reported in milliseconds (ms). RMSSD reflects short-term beat-to-beat heart rate variability.

Heart rate variability is assessed during a 10-minute resting measurement. The standard deviation of normal-to-normal intervals (SDNN) is calculated as the standard deviation of all normal-to-normal (NN) interbeat intervals during the analyzed recording and is reported in milliseconds (ms).

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. Absolute high-frequency (HF) power represents spectral power within the HF band of 0.15 to 0.40 Hz and is initially calculated in milliseconds squared (ms²). HF power is natural log-transformed [ln(HF Power)] for statistical analysis. Change is calculated as the post-intervention ln(HF Power) value minus the pre-intervention ln(HF Power) value.

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. The LF/HF ratio is calculated by dividing absolute low-frequency power by absolute high-frequency power. LF power is determined within the frequency band of 0.04 to 0.15 Hz, and HF power within the frequency band of 0.15 to 0.40 Hz. The LF/HF ratio is dimensionless and is natural log-transformed for statistical analysis. Change is calculated as the post-intervention ln(LF/HF ratio) value minus the pre-intervention ln(LF/HF ratio) value.

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. Relative high-frequency (HF) power represents the proportion of total spectral power occurring within the HF band of 0.15 to 0.40 Hz. It is calculated as HF power divided by total power and multiplied by 100 and is reported as a percentage (%). Change is calculated as the post-intervention value minus the pre-intervention value.

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. Relative low-frequency (LF) power represents the proportion of total spectral power occurring within the LF band of 0.04 to 0.15 Hz. It is calculated as LF power divided by total power and multiplied by 100 and is reported as a percentage (%). Change is calculated as the post-intervention value minus the pre-intervention value.

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. Absolute low-frequency (LF) power represents spectral power within the LF band of 0.04 to 0.15 Hz and is reported in milliseconds squared (ms²). Change is calculated as the post-intervention value minus the pre-intervention value.

Frequency-domain heart rate variability is assessed during a 10-minute resting measurement. Total power represents the overall spectral power of normal-to-normal (NN) interval variability across the prespecified analyzed frequency range. It is calculated as the sum of the spectral power in the very-low-frequency, low-frequency, and high-frequency bands and is reported in milliseconds squared (ms²). Change is calculated as the post-intervention value minus the pre-intervention value.

Heart rate variability is assessed during a 10-minute resting measurement. pNN50 is calculated as the number of pairs of successive normal-to-normal (NN) interbeat intervals that differ by more than 50 milliseconds, divided by the total number of successive NN interval pairs and multiplied by 100. The parameter is reported as a percentage (%). Change is calculated as the post-intervention value minus the pre-intervention value.

Cardiac autonomic regulation during controlled breathing is assessed using a 2-minute breathing test. Normalized respiratory sinus arrhythmia (RSAnorm) is derived from heart rate variability during the breathing test according to the prespecified analysis procedure. Higher values indicate a greater respiratory modulation of heart rate.