Thai Patients’ Drug Safety Knowledge and Perceptions Relating to Different Forms of Written Medicine Information: A Comparative Study

Figures & data

Table 1 Demographic Data of Patients Divided by Types of WMI Received

Demographic Characteristics	Number of Patients (%)			p-value*
	Total (n = 750)	PI Group (n = 375)	PIL Group (n = 375)
Gender
● Male	349 (46.5)	161 (42.9)	188 (50.1)	0.048
● Female	401 (53.5)	214 (57.1)	187 (49.9)
Age group
● 18–40	95 (12.7)	75 (20.0)	20 (5.3)	<0.001
● 41–65	495 (66.0)	233 (62.1)	262 (69.9)
● ≥ 66	160 (21.3)	67 (17.9)	93 (24.8)
Educational level
● < Bachelor’s degree	203 (27.1)	103 (27.5)	100 (26.7)	0.805
● ≥ Bachelor’s degree	547 (72.9)	272 (72.5)	275 (73.3)
Occupations
● Agriculture	92 (12.3)	39 (10.4)	53 (14.1)	0.014
● Civil servant	354 (47.2)	191 (50.9)	163 (43.5)
● Employee, private employee	46 (6.1)	27 (7.2)	19 (5.1)
● Own business	93 (12.4)	51 (13.6)	42 (11.2)
● Unemployed/student/not specified^a	165 (22.0)	67 (17.9)	98 (26.1)
Income
● ≤ 10,000 baht	162 (21.6)	87 (23.2)	75 (20.0)	0.474
● 10,001–30,000 baht	256 (34.1)	129 (34.4)	127 (33.9)
● >30,000 baht	332 (44.3)	159 (42.4)	173 (46.1)
Health insurance
● Universal Coverage Scheme	75 (10.0)	37 (9.9)	38 (10.1)	0.103
● Social Security Scheme	49 (6.5)	30 (8.0)	19 (5.1)
● Civil Servant Medical Benefit Scheme	585 (78.0)	282 (75.2)	303 (80.8)
● Self-pay	41 (5.5)	26 (6.9)	15 (4.0)
Underlying disease
● No underlying disease	114 (15.2)	66 (17.6)	48 (12.8)	0.219
● 1–2	488 (65.1)	234 (62.4)	254 (67.7)
● 3–4	126 (16.8)	62 (16.5)	64 (17.1)
● ≥ 5	22 (2.9)	13 (3.5)	9 (2.4)
Current medications
● None	116 (15.5)	67 (17.9)	49 (13.1)	0.282
● 1–2	166 (22.1)	80 (21.3)	86 (22.9)
● 3–4	211 (28.1)	99 (26.4)	112 (29.9)
● ≥ 5	257 (34.3)	129 (34.4)	128 (34.1)
History of receiving WMI prior to study
● None	477 (63.6)	235 (62.7)	242 (64.5)	0.865
● Received only PIs	167 (22.3)	86 (22.9)	81 (21.6)
● Received only PILs	106 (14.1)	54 (14.4)	52 (13.9)

Notes: *Pearson Chi-Square test was used to determine differences between groups; p < 0.05 with Bonferroni correction (p < 0.0006). Bold numbers of p-value indicate statistical significance with Bonferroni correction (p < 0.0006). ^aNot specified (n = 5).

Abbreviations: WMI, written medicine information; PI, package insert; PIL, patient information leaflet.

Table 2 Comparison of Correct Responses to Safety Knowledge Questions Between Receiving Package Inserts and Patient Information Leaflets

Items of Safety Knowledge	Total (n = 750)	PI Group (n = 375)	PIL Group (n = 375)	p-value*
Q1. Contraindication for taking the medicine
● Correct	512 (68.3)	277 (73.9)	235 (62.7)	0.001
● Incorrect	238 (31.7)	98 (26.1)	140 (37.3)
Q2. Precautions before taking the medicine
● Correct	397 (52.9)	160 (42.7)	237 (63.2)	<0.001
● Incorrect	353 (47.1)	215 (57.3)	138 (36.8)
Q3. Missed-dose management
● Correct	522 (69.6)	229 (61.1)	293 (78.1)	<0.001
● Incorrect	228 (30.4)	146 (38.9)	82 (21.9)
Q4. Non-serious side effects
● Correct	424 (56.5)	170 (45.3)	254 (67.7)	<0.001
● Incorrect	326 (43.5)	205 (54.7)	121 (32.3)
Q5. Serious side effects
● Correct	453 (60.4)	205 (54.7)	248 (66.1)	0.001
● Incorrect	297 (39.6)	170 (45.3)	127 (33.9)
Q6. Actions while taking the medicine
● Correct	492 (65.6)	211 (56.3)	281 (74.9)	<0.001
● Incorrect	258 (34.4)	164 (43.7)	94 (25.1)
Q7. Actions to avoid side effects/Overdosage management^a
● Correct	492 (65.6)	206 (54.9)	286 (76.3)	<0.001
● Incorrect	258 (34.4)	169 (45.1)	89 (23.7)
Q8. Medicine-specific information^b
● Correct	437 (58.3)	185 (49.3)	252 (67.2)	<0.001
● Incorrect	313 (41.7)	190 (50.7)	123 (32.8)
Knowledge levels^c
● Poor to moderate level	505 (67.3)	297 (79.2)	208 (55.5)	<0.001
● High level	245 (32.7)	78 (20.8)	167 (44.5)

Notes: *Pearson Chi-Square test was used to determine differences between groups, p<0.05 with Bonferroni correction (p<0.0006). ^aActions to avoid side effects for celecoxib-PIL, and overdosage for atorvastatin and metformin-PIL. ^bContraindication for celecoxib-PIL, dosage instruction for atorvastatin-PIL, and precaution for metformin-PIL. ^cKnowledge levels were categorized by low to moderate levels (< 7 points of 8), High level (≥ 7 points of 8). Bold values indicate significance at p<0.05 with Bonferroni correction (p<0.0006).

Abbreviations: PI, package insert; PIL, patient information leaflet.

Table 3 Multiple Logistic Regression Analysis of Factors Associated with Safety Knowledge About Medications

Factors	Number of Patients (%)		Adjusted Odds Ratio	Lower	Upper	p-value
	Low–Moderate Level (n = 505)	High Level (n = 245)
Type of WMI
● PI	297 (58.8)	78 (31.8)	1
● PIL	208 (41.2)	167 (68.2)	3.612	2.554	5.108	<0.001
Gender
● Male	250 (49.5)	99 (40.4)	1
● Female	255 (50.5)	146 (59.6)	1.524	1.096	2.119	0.012
Age group
● 18–40	64 (12.7)	31 (12.7)	1
● 41–65	317 (62.7)	178 (72.6)	0.763	0.462	1.260	0.291
● >65	124 (24.6)	36 (14.7)	0.403	0.218	0.747	0.004
Educational level
● < Bachelor’s degree	157 (31.1)	46 (18.8)	1
● ≥ Bachelor’s degree	348 (68.9)	199 (81.2)	1.863	1.260	2.754	0.002

Notes: Adjusted for type of WMI, gender, age group, educational level, occupations, income per month, history of drug allergy, and history of receiving WMI prior to study. Bold values indicate significance at p < 0.05 with Bonferroni correction (p < 0.0006).

Abbreviations: WMI, written medicine information; PI, package insert; PIL, patient information leaflet.

Table 4 Comparison of Consumer Rating Between Package Inserts and Patient Information Leaflets Using the Adapted CIRF

Items	PI Group (Median, Range) (n = 375)	PIL Group (Median, Range) (n = 375)	p-value*
Comprehensibility
● Read	3 (2–4)	4 (4–5)	<0.001
● Understand	3 (3–4)	4 (4–5)	<0.001
● Remember	3 (3–4)	4 (3–4)	<0.001
● Locate	3 (2–4)	4 (3–4)	<0.001
● Keep for the future	4 (3–4)	4 (4–5)	<0.001
Total (min-max: 7–25)	16 (14–19)	20 (17–22)	<0.001
Future use
● Read	4 (4–5)	5 (4–5)	<0.001
● Use	4 (4–5)	5 (4–5)	<0.001
● Keep	4 (3–5)	5 (4–5)	<0.001
Total (min-max: 3–15)	12 (11–14)	14 (12–15)	<0.001
Utility
● Indication	3 (3–4)	4 (3–4)	<0.001
● Contraindication	3 (3–4)	4 (3–4)	<0.001
● Direction	3 (3–4)	4 (3–4)	<0.001
● Precautions	3 (3–4)	4 (3–4)	<0.001
● Side effects	3 (3–4)	4 (3–4)	<0.001
● Storage	3 (3–4)	4 (3–4)	<0.001
Total (min-max: 6–24)	19 (17–22)	22 (19–24)	<0.001
Design
● Organization	4 (3–4)	4 (4–5)	<0.001
● Attractiveness	3 (2–4)	4 (3–5)	<0.001
● Print size	3 (2–4)	5 (4–5)	<0.001
● Tone	3 (3–4)	4 (3–5)	<0.001
● Helpfulness	4 (3–5)	5 (4–5)	<0.001
● Bias	4 (3–4)	4 (4–5)	<0.001
● Spacing	3 (2–4)	5 (4–5)	<0.001
Total (min-max: 7–35)	22 (19–26)	30 (25–34)	<0.001

Notes: *Mann Whitney-U test was used to determine differences between groups; p < 0.05 with Bonferroni correction (p < 0.0006).

Abbreviations: CIRF, consumer information rating form; PI, package insert; PIL, patient information leaflet.

Table 5 Comparison of Attitudes Towards the Information Provided in the WMI and Perception of Benefit and Risk from Taking the Medicines

Items	Overall (Median, Range) (n = 750)	PI Group (Median, Range) (n = 375)	PIL Group (Median, Range) (n = 375)	p-value*
1. Satisfaction with the information provided in WMI	7.80 (6.10–9.30)	7.10 (5.00–8.70)	8.30 (7.20–9.70)	<0.001
2. Benefit to health from taking the medicine	8.50 (7.00–10.00)	8.40 (5.00–8.70)	8.80 (7.50–10.00)	0.012
3. Risk to health from taking the medicine	5.00 (5.00–7.10)	5.00 (5.00–7.10)	5.00 (4.40–7.00)	0.222
4. Severity of side effects that would occur caused by taking the medicine	5.00 (3.60–7.23)	5.00 (3.70–7.20)	5.00 (3.40–7.30)	0.581
5. More benefit or more risk**	5.00 (2.48–6.80)	5.00 (2.15–6.20)	5.00 (2.80–7.15)	0.008
6. Intention to take the medicine	8.60 (7.00–10.00)	8.40 (6.30–10.00)	8.70 (7.40–10.00)	0.009

Notes: *Mann–Whitney U-test was used to determine differences between groups; **Higher scores indicate greater benefit. Bold values indicate significance at p < 0.05 with Bonferroni correction (p < 0.0006).

Abbreviations: WMI, written medicine information; PI, package insert; PIL, patient information leaflet.