Background Secondhand smoke (SHS) exposure can affect physical development in children. An understanding of parental risk perception of SHS could guide efforts to develop measures for prevention of SHS exposure among children. This study aimed to assess parental risk perceptions of SHS and action taken by parents to minimise SHS exposure in their children. Methods This cross-sectional nationwide study conducted in 2018 recruited convenience sample of 289 parents with children up to age 12 at public areas. Parents were asked to rate the risk level from 1 (no risk) to 5 (extremely high risk) by looking at photographs of an adult smoking in the presence of a child in 8 different situations. The implementation of smoking restriction rules was assessed. Mean scores were calculated with higher scores representing higher risk perception of SHS to child’s health. Linear regression analysis was used to determine factors associated with the level of parental risk perception of SHS exposure to their children’s health. Results A total of 246 parents responded. Their mean age was 35 years (SD 6.4). The majority were mothers (75.6%), Malays (72.0%) and had tertiary education level (82.5%), and non-smoker (87.1%). The mean age of respondents’ youngest child was 3 years (SD 3.1). The risk perception level was high [mean scores: 4.11 (SD: 0.82)]. Most parents implemented household (65.0%) and car (68.3%) smoking restriction rules. Lower levels of risk perception were observed among participants who were current smokers (p < 0.001), lived with a smoker (p < 0.001), allowed household smoking with an open window (p = 0.027). Conclusion Most parents perceived that risks of SHS exposure to their children were high but only two-thirds of them had set rules prohibiting smoking. Health policymakers should pay attention to factors associated with lower risk perception among parents. Trial registration This study was approved by the Medical Research Ethics Committee, Ministry of Health Malaysia (Registration Number: NMRR-18-3299-44967).

Background: Secondhand smoke (SHS) exposure can affect physical development in children. An understanding of parental risk perception of SHS aid in developing protectives measures to prevent children from SHS exposure. This study aimed to assess parental risk perceptions of SHS and action taken by parents in minimising their children from exposing to SHS.Methods: This cross-sectional nationwide study conducted in 2018 conveniently recruited 289 parents with children up to age 12 at the public areas. Parents were asked to rate the risk level from 1 (no risk) to 5 (extremely high risk) by looking at the photographs of an adult smoked in the presence of a child in 8 different situations. The implementation of smoking restriction rules was assessed. Mean score was calculated with higher scores represent higher risk of SHS to child’s health. Linear regression analysis was used to determine factors associated with the level of parental risk perception of SHS exposure to the children’s health.Results: A total of 246 parents responded. Their mean age was 35 years old (SD 6.4), majority were mothers (75.6%), Malays (72.0%), had tertiary education level (82.5%), and had a youngest child with mean age of 3 years (SD 3.1). The risk perception level was high [mean scores: 4.11 (SD: 0.82)]. Most parents implemented household (65.0%) and car (68.3%) smoking restriction rules. Negative risk perception level was observed among participants who were fathers with lower occupation class (p=0.005), lived with a smoker (p=0.023), allowed household smoking with open window (p=0.001), being a father and lived with a smoker (p=0.020), and mothers with managerial position while the fathers had a lower occupation class (p=0.038).Conclusion: Most parents perceived that risks of SHS exposure to their children was high but only two-thirds of them had set smoking prohibiting rules. Health policymaker should pay attention to tactors associated with negative risk perceptions among parents.Trial registration: This study is approved by Medical Research Ethics Committee, Ministry of Health Malaysia (Registration Number: NMRR-18-3299-44967).