• Sumalin Mooltichai Faculty of Pharmaceutical Sciences, Prince of Songkla University
  • Sanguan Lerkiatbundit Department of Pharmacy Administration, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Songkhla
  • Woranuch Saengcharoen Department of Clinical Pharmacy, Faculty of Pharmaceutical Sciences, Prince of Songkla University, Songkhla
Keywords: health literacy, understanding, patient information leaflet, paracetamol


This study aimed to test the understanding of patient information leaflets (PIL) for paracetamol by comparing persons with adequate health literacy (HL) levels and those with non-adequate HL levels and to determine a cut-off point of understanding the PIL of paracetamol. This study is a cross-sectional survey. The participants were randomly selected by convenience sampling in community areas in one district of Songkhla Province. There were 285 participants (143 in the tablet PIL group and 142 in the syrup PIL group). The study instruments were the Thai Health Literacy Assessment Using Word List to test HL and an interview form to test understanding of PIL. The results showed that for the tablet PIL group and the syrup PIL group, HL levels of participants were associated with the ability to understand the PIL (p < 0.001). The adequate HL group had significantly more understanding of the PIL than the non-adequate HL group in both PIL of tablets (54.0% and 23.8% respectively, p < 0.001) and PIL of syrup (50.8% and 11.7% respectively, p < 0.001). From analysis of the Receiver Operating Characteristic curve, the optimal cut-off point of HL was 37. Although it was found that the cut-off point of syrup PIL was 35, the specificity value was lower. In the cut-off point of 37, the area under the curve, sensitivity, specificity, positive predictive values and negative predictive values were 0.68, 64.20, 67.80, 54.00 and 76.20, respectively for PIL of tablet and those were 0.77, 78.60, 68.00, 50.80 and 88.30, respectively for PIL of syrup. In conclusion, persons with different HL levels were different in understanding the PIL of paracetamol among consumers. Therefore, in the development of PIL, the information should be thorough and specific enough that all persons of literacy levels will be able to comprehend it.This will result in people using paracetamol more safely.


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