การทดสอบความถูกต้องของแบบประเมินความแตกฉานด้านสุขภาพสำหรับชาวไทยชนิดรายการคำที่มีคำถามทดสอบความเข้าใจในผู้ป่วยชาวมุสลิม

Abstract

This study aims to test the Thai Health Literacy Assessment Using Word List with Extended Questions to Test Comprehension (THLA-W+) and to determine a cut-off of the test for judging the levels of health literacy in Muslim patients, and to determine cut-off value to interpret the level of health literacy (HL), and to compare the properties of the THLA-W+ calculating the score which obtained from the test in 3 methods (THLA-W+R, THLA-W+C and THLA-W+RC). The researcher used the THLA- W+ developed by Phadoong Chanchuto (2017). The scale consists of 48 words with 4 corresponding choices to test the comprehension of word meaning. Scoring of the scale were conducted in 3 methods: 1) calculating the score from reading test (THLA-W+R), 2) calculating the score from comprehension test (THLA-W+C), and 3) calculating the score from both reading and comprehension test (THLA-W+RC). The THLA-W+ was administered to 767 Muslim outpatients in Yaring hospital in Pattani province. The subjects completed THLA-W+, questionnaires on HL indicating variables and Thai Health Literacy Assessment Using Nutrition Label (THLA-N). The result showed that reliabilities of the THLA-W+R, THLA-W+C and THLA-W+RC were high as 0.982, 0.969 and 0.969 respectively. Validity of the scale was evident from the ability of the THLA-W+C and THLA-W+RC to discriminate the subjects with different levels of education. Their discriminating ability was better than that of the THLA-W+R. Correlation coefficient between the THLA-W+ scores from all three methods of calculation with HL indicators (eg, reading ability, understanding of health documents) was positive and statistically significant (r=0.222-0.816). The THLA- W+C and THLA-W+RC showed a higher correlation coefficient than the THLA-W+R did. Overall, those with correct response on the questions in HL indicators (eg, reading ability) obtained a higher level of THLA-W+ scores than those with incorrect answers did. THLA-W+C and THLA-W+RC were highly correlated with r=0.98. The analysis of the receiver operating characteristics (ROC) with reading ability, understanding of health documents and THLA-N as gold standards revealed that the THLA-W+R had an area under the curve (AUC) of 0.641-0.660 (depending on gold standards), which was less than the AUCS of the THLA-W+C and THLA-W+RC, which were 0.820-0.830 and 0.826-0.832, respectively. The result indicated that THLA-W+C and THLA-W+RC were more accurate in classifying the levels of HL than THLA-W+R was. The cut-off value of the THLA-W+R, THLA-W+C and THLA-W+RC were 47, 37 and 37 respectively. Sensitivities of the scales were 41.9-46.5, 68.7-78.6 and 70.7-80.7 respectively. THLA-W+C and THLA-W+RC were more sensitive than THLA-W+R. Specificities of three measures were similar at 76.21-88.10, 67.96-83.33 and 66.02- 80.95, likelihood ratio for a positive more than one which indicates to advantages of screening test. The THLA-W+ was reliable and valid for using in Muslim patients. Scale should be administered as comprehension test alone because it gives the scores with a better psychometric property than the reading test. Moreover, it simplifies testing process and required no staff to judge the pronunciation of the subjects. The THLA- W+C shows a satisfactory sensitivity and specificity with the score of 37 or lower indicating inadequate HL.