Table 2. Overview of characterises of self-administered measures.

Instrument	Captures	Measured at:	Time to self-administer	Planned Scoring	Interpretation (↑, higher score)
Standard Shiftwork Index (SSI) [32]	Work context and shift system details General job satisfaction [33] Sleep Chronic Fatigue Physical health Psychological health (General health questionnaire) [34] Cognitive-somatic Anxiety [35] Social and domestic situation Coping Circadian rhythm type (Composite morningness questionnaire) [36] Circadian type (Circadian type inventory) Eysenck Personality Inventory [37]	T0, T1, T2, T3, T4	30 mins	Job satisfaction: 0–7 Sleep disturbance: 0–5 Chronic Fatigue: 5–50 Digestive health: 8–32 Cardiovascular health: 8–32 Psychological wellbeing: 0–36 Cognitive anxiety: 7–35 Somatic anxiety: 7–35 Social and domestic satisfaction: 21–105 Morningness Scale: 13–55 Circadian languidity: 10–50 Circadian flexibility: 8–40 Neuroticism: 6–24 Extraversion: 6–24	↑ = more satisfied ↑ = sleep disturbance ↑ = more fatigue ↑ = digestive problems ↑ = cardiovascular problems ↑ = poorer psychological health ↑ = greater anxiety ↑ = greater anxiety ↑ = more satisfaction ≤ 22 evening type 23–43 intermediate type ≥ 44 morning type ↑ = more circadian languidity ↑ = higher circadian flexibility ↓ = higher neuroticism ↓ = high extraversion
Shift work disorder screening questionnaire [38]	4-item screening tool to aid in diagnosis of shift work disorder.	T0, T1, T2, T3, T4	~5 mins	In accordance with criteria specified by the developing authors [38]	↑ = likelihood of SWD
Short Form General Health survey (SF-20) [39]	20-item measures of physical functioning and wellbeing.	T0, T1, T2, T3, T4	~5 mins	Physical Functioning: 0–100 Role Functioning: 0–100 Social Functioning: 0–100 Mental Health: 0–100 Health Perceptions: 0–100 Pain: 0–100	↑ = better health
Pittsburgh Sleep Quality Index (PSQI) [40]	Assess sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication and daytime dysfunction for previous 30 days.	T0, T1, T2, T3, T4	5–10 mins	Global Sleep Score: 0–21 Subjective Sleep Quality: 0–3 Sleep latency: 0–3 Sleep duration: 0–3 Habitual sleep efficacy: 0–3 Sleep disturbances: 0–3 Sleep medication: 0–3 Daytime dysfunction: 0–3	↑ = poorer sleep quality Global sleep score > 5 = clinically poor sleep
Occupational Fatigue and Exhaustion Recovery Scale (OFER15) [41]	15-item scale measuring chronic work-related fatigue, end-of-shift states and recovery between shifts.	T0, T1, T2, T3, T4	5 mins	Chronic faituge:0–100 Acute fatigue: 0–100 Inter-shift recovery: 0–100	↑ = more chronic fatigue ↑ = more acute fatigue ↑ = more recovery between shifts
International Physical Activity Questionnaire (IPAQ) [42]	27-item measure of physical activity for past seven days. Job-related physical activity, transportation, housework/house maintenance/family caring, sport/leisure time activity and sedentary time.	T0, T1, T2, T3, T4	15–20 mins	Walking: 3.3 METs Moderate activity: 4 METs Vigorous activity: 8 METs	↑ = more physical activity or more intensive physical activity May be categorised in to High, Moderate Low Physical Activity levels
Post-traumatic stress disorder checklist for DMS-5 (PCL-5) [43]	20-item measure that assess DMS-5 symptoms of post-traumatic stress disorder.	T0, T1, T2, T3, T4	5–10 mins	Symptom severity:0–80	↑ = higher symptom severity
Newest Vital Sign (NVS) [44]	6-item measure of health literacy, using nutritional label.	T0, T1, T2, T3, T4	3 mins	Health Literacy: 0–6	↑ = better health literacy
Shift worker risk perception questions	5-item measure intended to measure health risk perception in shift workers	T0, T1, T2, T3, T4	3 mins	Health risk perception: 5–25	↑ = higher levels of perceived health risk
Sleep diaries– 7 days	24-hour period. Time to bed, time asleep, time awake, time out of bed, total sleep time, waking during sleep period, length of waking, sleepiness prior to sleep, sleepiness upon waking, self-report sleep quality, naps (Y/N), length of naps (if relevant).	T0, T1, T2, T3, T4	~5 mins	Total sleep time Time in bed Sleep latency Sleepiness prior to bed Sleepiness on waking Sleep quality Naps	NA
NASA Task load (NASA-TLX) [29]– 7 days (when on shift)	Shift start/finish time. 6-item workload assessment measuring mental demand, physical demand, temporal demand, performance, effort, frustration.	T0, T1, T2, T3, T4	~3 mins	Workload: 0–100	↑ = higher workload Low: 0–9 Medium: 10–29 Somewhat high: 30–49 High: 50–79 Very high: 80–100

Note. DSMV = Diagnostic and Statistical Manual of Mental Disorders, METs = Metabolic equivalent of task.