Table 1.

Summary of included studies which reported an observation and self-report measure of health protective behaviour

Study	Population; location	Observed prevalence	Self-report prevalence
Henry (1992) [62]	ED physicians (12 staff plus rotating residents), medical students, nursing staff, and ancillary personnel; hospital emergency department	Overall face covering wearing adherence: 1.2%	Overall face covering wearing adherence: 25.5%
Raymond (2001) [63]	Tattoo artists; Minneapolis and St. Paul, MN	Overall adherence was 71%	Overall adherence was 83%
Cohen (2002) [64]	Dermatologists; outpatient dermatology clinics in Israel	7 (38.5%) physicians washed hands only after contact with suspected infected material and 1 (7.7%) before each physical examination. Seven physicians (53.9%) washed their hands 1–5 times a day	19 (37.3%) washed their hands only following contact with material suspected of being contaminated, 18 (35.3%) prior to examining every patient, 14 (27.5%) wash hands 1–5 times a day
Moret (2004) [65]	Healthcare workers (physicians, nurses, and nurse assistants); French university hospital	Overall adherence was 74%	Overall adherence was 74%
Snow (2006) [66]	60 students enrolled in a certified nursing program; on day 1 and day 30 of the clinical rotation.	Day 1. Student hand hygiene:49.1%. Day 30. Student hand hygiene:52.3%.	Based on a scale of 10-100. 10 being lowest possible commitment to handwashing. On day 30 students reported 93.0 before patient contact, 95.5 after patient contact, 84.9 before donning gloves, and 95.1 after removal of gloves.
Alemayehu (2009) [67]	Third and fourth year students; U.S. medical school over one academic year at the beginning of every core rotation (medicine, surgery, primary care medicine, paediatrics, obstetrics/gynaecology, neurology, psychiatry)	Overall adherence: 87.9%	Overall adherence: 87.9%
Soyemi, C (2010) [68]	Doctors and nurses; three types of hospitals, i.e., public, security forces, and private, in Eastern Saudi Arabia.	Overall adherence for physicians: 27% Overall adherence for nurses: 29%	Likert scale. Physicians mean self-report was 10.19/15 based on 3 hand hygiene opportunities, and nurses was 13.65/15 based on 3 opportunities.
Jessee (2013) [69]	Staff on 3 medical/surgical units; a 600-bed academic medical centre (AMC) and a 110-bed community medical centre (CMC) in the South-eastern United States	Hand hygiene before glove application, was present in 14% of the CMC and 21% of the AMC staff Hand hygiene on room exit was 25 and 78% respectively.	Hand hygiene before glove application was present in 63% CMC and 50% of AMC staff. Hand hygiene on room exit 16 was 84 and 94% respectively.
Kim (2013) [70]	Doctors; healthcare settings.	Adherence at baseline: 49.7% Adherence in fourth quarter of 2012: 82.3%	Adherence at baseline: 82.9% Adherence in fourth quarter of 2012: 93.8%
Dalen (2013) [71]	Doctors (13%), nurses (70%), housekeeping staff (9%) and visitors of patients (9%); cancer hospital.	Overall hand hygiene adherence, nurses: 47% Overall hand hygiene, doctors: 51%	Overall hand hygiene adherence, nurses: 88% Overall hand hygiene adherence, doctors: 85%
Lakshmi (2015) [72]	Healthcare workers (predominantly nurses); ICU in an oncology, BMT and neurosurgical centre in South India.	Use of alcohol based hand rub 98.5%, 5 moments of hand hygiene 88.5%, 6 steps of hand hygiene 65%.	Use of alcohol based hand rub 98.5%, 5 moments of hand hygiene 88.5%, 6 steps of hand hygiene 92.5%
O’Donoghue (2016) [73]	Healthcare workers, 76 radiographers, 17 nurses, and nine healthcare assistants; a radiography unit.	Overall adherence: 29% Post-test adherence: 51%	‘I wash my hands after using the rest room’ was rated a median of 5/5 on a Likert scale, quartiles 4-5 before and after intervention.
Galiani (2016) [74]	General public; households and community settings in Peru	Handwashing with soap was observed in only 16% of the events that required it. 20% of faecal contact events, 25% of eating events, 6% of child feeding events, and 10% of food preparation events.	Less than 50% reported hand washing at times of faecal contact. 39% reported with toilet use, 34% cleaning up after children, 68% when cooking or with food preparation and 31% when feeding a child.
Keller (2018) [75]	ED staff, 100 nurses, 13 staff emergency physicians, 25 medical interns, and various other professions (e.g. maintenance and nursing assistants). Non-ED consulting physicians and surgeons regularly visiting the ED; in an Emergency Department of the University Hospital Zurich	Hand hygiene adherence during baseline: 56%. Hand hygiene adherence during intervention: 64%	Hand hygiene adherence during baseline: 4.12. Hand hygiene during intervention 4.03 (on a Likert scale 1-5, 5 being always)
Baloh (2019) [76]	Healthcare workers; 3 large academic US hospitals	Hand hygiene before gloving was performed 42% of the time	Hand hygiene before gloving was reported 88% of the time
Le (2019) [77]	Healthcare workers (physicians, nurses, care assistants, and student nurses); large central hospital in Vietnam	Physicians overall hand hygiene adherence:14.6%. Nurses overall hand hygiene adherence: 38.8%	Physicians overall hand hygiene adherence: 67.2%. Nurses overall hand hygiene adherence: 97.8%
Woodard (2019) [78]	Healthcare workers (nurses, physicians, technicians) and patient interactions; 750-bed tertiary care hospital in Baltimore, Maryland.	Overall hand hygiene adherence: 35% of all opportunities. Overall entry and exit hand hygiene adherence: 90%	81% of the sample estimated they miss performing hand hygiene when they realize it should be performed 10-20% of the time. An additional 11% reported missing hand hygiene 30-40% of the time. 4% estimated they missed performing hand hygiene 90-100% of the time.
Kelcikova (2019) [79]	Doctors and nurses; eight hospitals in two countries (five in Slovakia and three in the Czech Republic)	Overall adherence: 67.7%	Overall adherence: 74.0%
Derksen (2020) [50]	Healthcare workers (physicians, midwives, and nurses); two German obstetric hospitals during and after the onset of the COVID-19 pandemic.	After declaration of pandemic overall hand hygiene adherence: 95%. After body fluid exposure risk: 100%.	After declaration of pandemic overall hand hygiene adherence: M = 5.03, SD = 0.75 on a 6 point scale. After body fluid exposure risk: M = 5.66, SD = 0.67.
Dowding (2020) [51]	400 U.S. home care nurses; community care organization	Overall hand hygiene adherence: 45.6%.	Overall hand hygiene adherence: 99.4%
Skuntaniyom (2021) [24]	119 healthcare workers (mostly nurses and laboratory workers) and 100 general public (mostly administrative workers and professionals); Thailand in two inpatient hospitals providing COVID-19 testing and treatment.	100% of patients and 100% healthcare workers wore face covering correctly. 35.2% of patients and 40.0% of healthcare workers correctly cleaned all areas of both hands.	86% of patients and 95.8% of healthcare workers wore a face covering correctly. 67% of patients and 84.9% of healthcare workers reported adhering to hand hygiene.