Table 2.

Characteristics of included studies

Author	Study Setting	Methodological issues	Quality score (%)	Factor (exposure)	Outcome	Results
Bou-Mitri et al. [15]	Lebanese private and government hospitals	Cross-sectional (n = 254; M = 162, F = 92) Non-random sampling Self-reported food handling practices (SRFHPs)	75	Gender Work experience Education Training Premises type (government or private) Location	SRFHPs	Reported significantly higher scores concerning SRFHPs (a) of men in comparison to women, (b) of food handlers who worked in government hospitals than those in private hospitals and (c) in relation to work experience. Grand KAP scores were significantly higher among food handlers in government hospitals than those in private ones. Training significantly associated with knowledge but not with attitudes, practices and overall KAP. Age, education and hospital location were not significantly related to knowledge, attitudes, practices or grand KAP scores.
De Souza et al. [23]	Restaurants food handlers in Brazil	Cross-sectional, Small sample (n = 70; M = 52, F = 18) Study limitations not outlined	75	Knowledge Gender Work experience Education Training	SRFHPs and observed food handling practices (OFHPs)	Reported a positive correlation between food safety knowledge and SRFHPs. No correlation between: (i) socio-demographic characteristics and SRFHPs and (ii) training and SRFHPs. Reported no correlation between food safety knowledge and OFHPs. OFHPs had no correlation with SRFHPs.
Vo et al. [24]	Canteens in Southern Vietnam	Cross-sectional (n = 909; M = 217, F = 692)	92	Education Knowledge Attitudes	SRFHPs and OFHPs	Reported no significant association between attitudes and SRFHPs Knowledge and education were associated with SRFHPs.
Zanin et al. [25]	Seafood workers in Brazil	Cross-sectional (n = 193; M = 165, F = 28) SRFHPs Study limitations not outlined Non-random sampling used	67	Age Education Work experience Knowledge Attitudes	SRFHPs	Reported significant positive correlation of SRFHPs with attitudes and age of the workers. No correlation of SRFHPs with knowledge, work experience and education.
Kunadu et al. [26]	Institutional food handlers in Ghana	Cross-sectional, (n = 278; M = 67, F = 211) SRFHPs		Gender Education Marital status Knowledge Attitudes	SRFHPs	Reported significant positive correlations between: (i) knowledge and attitudes, (ii) knowledge and SRFHPs and, (iii) attitudes and SRFHPs. Gender, education and marital status were not significantly related to SRFHPs.
Husain et al. [27]	School canteen food Handlers in Malaysia	Randomized controlled trial Small sample size (n = 79) No description of research ethics	83	Training	SRFHPS and OFHPs	Following implementation of food safety training, the SRFHPs in the intervention group were significantly higher compared to baseline. Reported a significant within-group and between-group improvement of OFHPs due to the training intervention.
Shuvo [28]	Biscuit industry, Bangladesh	Cross-sectional, (n = 110; M = 50, F = 60) SRFHPs Study limitations not outlined	75	Gender Knowledge Training	SRFHPs	Reported significant positive correlation between: (i) knowledge and SRFHPs, (ii) attitudes and SRFHPs, (iii) gender and SRFHPs, and (iv) food safety training and SRFHPs.
Jeon et al. [29]	Restaurants food handlers in South Korea	Cross-sectional (n = 140, M = 81, F = 59) SRFHPs No description of research ethics	75	Age Gender Education Income Work experience	SRFHPs	Reported significant differences in SRFHPs among (i) different age groups, (ii) educational levels and (iii) income levels. No significant differences in SRFHPs were reported in relation to the food handlers’ gender and work experience
Chen et al. [30]	Dairy plant workers in China	Cross-sectional (n = 194, M = 83, F = 110) Non-random sampling SRFHPs	75	Education Work experience Attitude Knowledge	SRFHPs	Reported a significant correlation between (a) attitudes and knowledge, (b) attitudes and SRFHPs (behaviour), (c) education with knowledge, attitudes and SRFHPs. No association between (a) attitude and SRFHPs (b) knowledge and SRFHPs and (c) work experience with knowledge, attitudes and behaviour.
Asmawi et al. [31]	Food courts in Malaysia	Cross-sectional (n = 108) SRFHPs	83	Knowledge Attitude	SRFHPs	Reported a significant correlation between (a) knowledge and attitude, (b) knowledge and SRFHPs, and (c) attitude and SRFHPs.
Derso et al. [12]	Ethiopian restaurants	Cross -sectional (n = 417, M = 93, F = 324) SRFHPs Study limitations not presented	75	Training Education Work experience Type of handwashing Age Gender Marital status	SRFHPs	Reported that factors significantly associated with SRFHPs were food safety training, education, work experience, and type of handwashing.
Woh et al. [32]	Migrant food handlers in Malaysia	Cross-sectional (n = 383, M = 364, F = 19) SRFHPs Non-random sampling	75	Gender Age Marital status Training Education Knowledge	SRFHPs	Reported a significant association between (a) training and SRFHPs, (c) knowledge and country of origin, and (d) education and knowledge Gender, age, marital status, education and knowledge were not significantly related to SRFHPs.
Al-Shabib et al. [33]	Food handlers from a university in Saudi Arabia.	Cross-sectional, Small sample (n = 87; all male) SRFHPs, No details of piloting and reliability status data collection instrument, and study limitations.	42	Knowledge Training Attitudes Work experience	Practice	Reported significant positive correlation between (a) knowledge and attitudes, (b) knowledge and training, (c) knowledge and personal hygiene (practices), (d) training and personal hygiene (e) attitudes and personal hygiene. No significant association was found between (a) work experience and knowledge, and (b) training and attitude. NB. Study did not report on the association between work experience and practices.
Ismail et al. [34]	Mobile food handlers in Malaysia	Cross-sectional (n = 320; M = 168, F = 150) SRFHPs No details of piloting and reliability status data collection instrument, study limitations and ethical issues	50	Knowledge	SRFHPs	Reported that standardized beta coefficient showed food safety knowledge as strongly influencing food safety practices
Mohd. Firdaus Siau et al. [35]	Food courts in Malaysia	Cross-sectional, (n = 274, M = 193, F = 81) SRFHPs No description of ethics and the study’s limitations	75	Age Education Training Knowledge Attitudes KAP	SRFHPs	Reported a significant correlation between (a) education and practices, (b) education and attitudes, (c) knowledge and attitudes, (e) attitudes and SRFHPs, (f) age and knowledge, and (g) training and knowledge. Study did not report on association between (a) training and SRFHPs, and (b) age and SRFHPs.
Adesokan, Raji [36]	Meat processing plants in Nigeria	Cross-sectional, (n = 190, M = 133, F = 57) SRFHPs Non-random sampling	67	Premises type (government or private) Gender Age Work experience Education Attitude	SRFHPs	Reported that the demographic variables with a significant effect on meat handling practice were age, gender, education and work experience. Reported significant relationship of (a) plant type with knowledge on meat handling and with meat handling practices (b) attitudes and practices
Tessema et al. [37]	Food and drinking premises in Ethiopia	Cross-sectional (n = 406, M = 151, F = 255) No description of the study’s limitations	83	Marital status Monthly income Knowledge Presence of insects and rodents Existence of shower and separate dressing room	OFHPs	Factors significantly associated with food safety practices were marital status, monthly income, knowledge, presence of insects and rodents and existence of shower and separate dressing room.
Sani, Siow [8]	Malaysian University cafeterias and canteens	Cross-sectional, (n = 112; M = 83, F = 29) SRFHPs Non-random sampling.	83	Attitudes Knowledge	SRFHPs	Reported significant positive correlation between (a) knowledge and attitudes, (b) knowledge and SRFHPs, and (c) attitudes and SRFHPs.
Da Cunha et al. [14]	High risk food premises in Brazil (meat products and raw salad)	Cross-sectional, (n = 183; M = 63, F = 120), No description of research ethics	83	Knowledge Training Work experience Meals served by a food handler Adequacy of buildings and facilities Nutritionist	SRFHPs and OFHPs	Variables significantly associated with use of observed desirable food handling practices were: (a) knowledge (b) work experience, (c) number of meals (d) Adequacy of buildings and facilities, (e) the nutritionist’s presence. No significant difference in food handling practice (whether observed or self-reported) or attitudes was found due to training or lack of training of food handlers.
McIntyre et al. [5]	Food handlers in British-Colombia, Canada.	Cross-sectional (n = 698, M = 264, F = 434) SRFHPs No details of piloting and reliability status data collection instrument.	67	Training Place of employment Education	SRFHPs	Trained food handlers’ self-reported handwashing practices were significantly better compared to untrained ones. Workers with tertiary education (college and university) had significantly higher food safety knowledge than those without.
Ko [38]	Restaurants food handlers in Taiwan	Cross-sectional (n = 421, M = 232, F = 189) Non-random sampling SRFHPs No description of research ethics	67	Knowledge Attitudes	SRFHPs	Reported significant positive relationship between (a) knowledge and attitudes, (b) attitudes and SRFHPs. Relationship between knowledge and SRFHPs was statistically insignificant.
Aziz, Dahan [39]	Malaysian school canteens food handlers	Cross-sectional (n = 364, M = 86, F = 278) SRFHPs No details of piloting and reliability status data collection instrument and ethical issues.	50	Attitudes	SRFHPs	Reported that food handlers’ attitude has a positive and significant impact on SRFHPs.
Tan et al. [40]	Food handlers in primary schools in Malaysia	Cross-sectional, Small sample (n = 85; M = 13, F = 72) Study limitations not outlined	75	Gender Age Work experience Education Knowledge Attitudes Glove use	SRFHPs and OFHPs	Reported that demographic variables with a significant effect on self-reported hand hygiene practice were gender and education. Reported positive correlation between (a) knowledge on food contamination and handwashing practice, (b) mean hand hygiene knowledge and hand hygiene scores No significant correlation of (a) attitudes with handwashing practice, (b) attitudes and personal hygiene, (c) work experience and hand hygiene practices, (d) age and handwashing practices.
Kibret, Abera [2]	Ethiopian food service premises	Cross-sectional (n = 455, M = 121, F = 334)	92	Gender Age Education Training License status Type of premise	Practices Sanitary conditions	Reported significant positive correlation between (a) training and practices, (b) license status and sanitary conditions, (c) type of premise (hotel, cafe, restaurant and juice house) and sanitary conditions, (d) training and food safety practices. No significant association was found between demographic variables (gender, age, education) and practices
Abdul-Mutalib [41]	Restaurants in Malaysia	Cross-sectional, Small sample (n = 64; M = 16, F = 48) Non-random sampling SRFHPs, No details on study limitations and ethical issues.	50	Gender Age Work experience Education Knowledge Attitudes	SRFHPs	Reported a significant correlation between (a) education and attitude, (b) knowledge and attitude, (c) knowledge and SRFHPs, and (d) attitude and SRFHPs. Gender, age, and experience level were not significantly related to the knowledge, attitudes or SRFHPs. Education was not significantly associated with SRFHPs.
Rahman et al. [11]	Street vendors in Malaysia	Cross-sectional (n = 361, M = 171, F = 190) Non-random sampling SRFHPs	75	Age Knowledge Attitude Training	SRFHPs	Reported that (a) age significantly influences food safety knowledge (FSK), (b) FSK and training influence attitudes, (c) FSK, training, attitudes and age influence SRFHPs. The marital status was not significantly related to food safety practices.
Ansari-Lari et al. [42]	Meat processing plants in Iran	Cross-sectional, Small sample (n = 97; M = 89, F = 8) SRFHPs Non-random sampling No details of piloting and reliability status data collection instrument and ethical issues.	42	Knowledge Attitudes Work experience Education	SRFHPs	Reported significant positive correlation between (a) knowledge and attitudes, (b) knowledge and education, (c) work experience and SRFHPs A significant negative correlation reported between (a) knowledge and SRFHPs, and (b) attitudes and SRFHPs.
Park et al. [13]	Restaurants in Korea	Pre-test post-test study Small sample (n = 90, M = 31, F = 59) Non-random sampling	75	Training Knowledge Attitudes	SRFHPs	A significant negative correlation (a) knowledge and practices, and (b) attitudes and practices. Non-significant correlation (a) training and knowledge, (b) training and food safety practice, (b) training and practices, and (c) food safety knowledge and sanitation management performances