A Survey of Pharmacists and Other Healthcare Professionals in Vietnam: Factors Influencing Knowledge and Attitudes Toward Reporting Adverse Drug Reactions

Abstract

Background:

Knowledge and attitudes of healthcare professionals are significant factors that affect the reporting of adverse drug reactions (ADRs). No previous research has examined the predictors of knowledge and attitudes toward ADR reporting in Vietnam.

Objectives:

The aim of this study was to examine the factors (ie, demographic and job-related characteristics) associated with inadequate knowledge and negative attitudes toward ADR reporting in a Vietnamese public hospital.

Methods:

A survey recruited a cross-sectional sample of 511 healthcare professionals (with a response rate of 92.9%) at a public hospital in Vinh Long province, Vietnam, from December 2022 to February 2023, using a self-administered questionnaire. Factors related to knowledge and attitudes toward ADR reporting were identified using univariate and multivariate logistic regression.

Results:

Pharmacists had significantly lower knowledge scores (mean = 5.86) than medical practitioners (7.24) and nurses (6.72). Additionally, pharmacists’ attitudes scored significantly lower (34.61) than those of medical practitioners (37.21) and nurses (36.86). Multivariate logistic regression showed that educational level, healthcare profession, monthly on-call shifts, and number of direct patient interactions were factors associated with a lower level of knowledge regarding ADR reporting. Additionally, age group and healthcare profession were identified as factors associated with negative attitudes toward ADR reporting among healthcare workers.

Conclusions:

Our study identified several factors associated with lower levels of knowledge and negative attitudes toward ADR reporting among healthcare workers in Vietnam. These findings highlight the need for targeted interventions and education programs to improve healthcare workers’ knowledge and attitudes toward ADR reporting.

Introduction

According to the World Health Organization, ¹ an adverse drug reaction (ADR) is defined as “any response to a drug which is noxious and unintended, and which occurs at doses used in man for prophylaxis, diagnosis, or treatment.” ADRs can occur in all healthcare facilities, especially in hospitals, due to the higher level of risk associated with hospital treatment. ² ADRs represent a significant public health issue associated with increased mortality rates, morbidity, costs, hospitalization rates, and lengths of hospital stay.^3-5 Studies conducted in the late 1990s and early 2000s reported that ADRs are the most common cause of hospitalization and one of the 6 leading causes of death.^3,6,7 In the European Union, ADRs cause 197 000 deaths annually. ⁸ The financial impact of ADRs is difficult to estimate accurately, but recent studies have estimated the cost to be between 75 to 180 billion US dollars per year for adults alone. The total number of hospital admissions due to ADRs has remained unchanged at approximately 5% for the past 30 years. ⁹

There are several methods for detecting and monitoring ADRs, among which, voluntary ADR reporting by healthcare professionals at hospitals is the simplest, least expensive, and most widely used method. ¹⁰ Voluntary ADR reporting is a fundamental and essential component of the pharmacovigilance system. ¹¹ Voluntary reporting systems are inexpensive and easy to operate, while forming the backbone of the World Health Organization’s (WHO) global database. ¹⁰ In Vietnam, ADR reporting from healthcare facilities is the primary source of data in the voluntary reporting system stored at the National Drug Information and ADR (DI & ADR) Center.

However, there are still issues preventing the complete and accurate reporting of ADRs, including underreporting both in terms of the frequency and qualities of ADRs. ¹² Incomplete reporting of ADRs is a common problem in many countries, particularly those with low to middle-income levels.^13-15 In Vietnam, in 2022, the National DI & ADR Center and the Ho Chi Minh City Regional DI & ADR Center received and processed 19 591 reports (representing 199 reports/1 million population). Among these, 14 942 ADR reports were sent from healthcare facilities, 2711 ADR reports occurred on Vietnamese territory from pharmaceutical manufacturing and business units, and 1955 reports of serious adverse events were from clinical trials conducted in Vietnam. ¹⁶ According to reports of the National DI & ADR Center, in Vinh Long province, there were only 12.4 reports per million population in 2022, a relatively low number compared to other provinces and cities in Vietnam. ¹⁶

The principal prerequisite for ADR reporting is being a practicing healthcare professional (HCPs), in which the knowledge and attitude of HCPs are important factors affecting the accuracy of ADR reporting.^14,17 Poor knowledge and negative attitudes can lead to ineffective ADR reporting. ¹⁸ The proportion of HCPs with poor knowledge about ADR varies with country, with rates being reported as 83.1% in Pakistan, ¹⁹ 75.4% in Ethiopia, ²⁰ and 57.2% in Malaysia. ²¹ Regarding attitudes, the proportion of HCPs with negative attitudes toward ADR reporting has been reported as 41.7% in Ethiopia ²⁰ and 26.9% in Malaysia. ²¹ Each study in this field uses a different methodology, resulting in different factors related to knowledge and attitudes being identified. Adegbuyi et al found that factors related to ADR knowledge included gender, the role of the healthcare professionals, and the facility level. ¹² Kassa Alemu and Biru found that nurses, health officers, and physicians were less likely to have adequate knowledge of ADR reporting compared to pharmacy professionals. ²⁰ Similarly, Adisa and Omitogun identified marital status, previous training, and HCP role as being factors associated with ADR knowledge. ²²

Over time, through the evolution of pharmaceutical work in hospitals in general and ADR monitoring activities in particular, the Vietnamese healthcare sector has introduced significant amounts of legislation aiming to implement practical ADR monitoring in hospitals, for example, Pharmacy Law No. 105/QH13, Decree No. 131/ND-CP, and Decision No. 29/QD-BYT.^23-25 This legislation provides a basis for enhancing the knowledge, attitudes, and practices of healthcare staff associated with reporting ADRs. To the best of our knowledge, no previous research has examined the predictors of knowledge and attitudes toward ADR reporting in this country. To address this knowledge gap, the present study sought to investigate the associations between demographic characteristics and job-related factors, and inadequate knowledge about and unfavorable attitudes toward ADR reporting, in a public hospital context in Vinh Long, Vietnam.

Methods

Study Design and Setting

This study used a cross-sectional descriptive design with a self-administered questionnaire. Data collection was conducted among healthcare professionals at a public hospital in Vinh Long province, Vietnam. Vinh Long province is located in the Mekong Delta region, ²⁶ approximately 135 km southwest of Ho Chi Minh City. ²⁷ Vinh Long’s economy is growing rapidly compared to that of other provinces in Vietnam. In 2021, the province had a population of around 1 029 000 people, served by 739 doctors, with over 77% of the population living in rural areas. ²⁸ The research site hosts 900 hospital beds, and from 2018 to 2021, the hospital has provided medical examinations and treatment for over 350 000 patients each year. ²⁹ In 2022, a total of 4 ADR cases were reported.

The sample size for the study was determined using the Raosoft^® sample size calculator, ³⁰ which estimated the requirement for a minimum of 317 participants assuming a 95% confidence level, a 5% margin of error, and a response distribution of 70.2% based on the findings of Hussain et al. ³¹

The study population included all healthcare workers, including medical practitioners, nurses, pharmacists, and others (midwives, engineers, accountants, and technicians), ³² working at this hospital between December 2022 and February 2023. The term medical practitioner refers to a person possessing a medical practice certificate and practicing medical examination and treatment. ³³ Meanwhile, nursing is an integral part of the healthcare system, requiring close coordination with other healthcare professions to enhance health, prevent illness, provide comprehensive care, and restore function for individuals of all ages in healthcare facilities and community health settings. Nursing also encompasses activities in end-of-life care, scientific research, involvement in health policy direction, patient management, healthcare system management, and health education. ³⁴

In Vietnam, as is the case globally, pharmacists assume a vital position in the healthcare system, encompassing diverse responsibilities. They serve as crucial sources of medication information and counseling, ensuring optimal patient care. Pharmacists undertake the management and assurance of medication safety and quality, extending beyond pharmaceuticals to encompass vaccines and medical devices that necessitate specialized expertise in their usage and associated risks. ³⁵ Moreover, they actively engage in pharmaceutical research and development, while also contributing to the education and training of future healthcare professionals. ³⁶ Within the hospital setting, pharmacists fulfill vital roles that encompass various domains in the field, including administration, pharmacy office work, drug storage and distribution, pharmacy statistics, clinical pharmacy, and outpatient drug distribution. ³⁷ In addition, in relation to clinical pharmacy activities, clinical pharmacists perform specific tasks, including participating in drug surveillance, developing Standard Operating Procedures (SOPs) in hospitals, providing medication information to healthcare personnel, and participating in the drugs and therapeutics committee. They also play a crucial role in constructing medication protocols, evaluating medications for patients, and providing medication counseling services to patients and nurses, while collaborating with physicians to optimize treatment regimens for patients. ³⁸ Pharmacists participating in the present study are also involved in all of these professional activities within the hospital setting.

A whole population sampling method was used. Based on the total staff list across all departments responsible for reporting ADRs in the hospital, the research team sent a total of 550 questionnaires to the leaders of all 17 departments to invite them and all staff to participate in the study. Participation was voluntary, and those who agreed were asked to complete the survey taking 20 minutes, with the results being collected on the same visit. Staff who were willing to participate, but unable to complete the survey during this initial visit, were left with a copy of the questionnaire and the request to complete it within 3 days when it would be collected.

Data Collection Instrument

A questionnaire was developed for self-administration in print form, based on a review of the previous literature.^39-43 Three experts in the field of pharmacovigilance and ADR were invited to assess the content validity of the questionnaire. A pilot study was conducted in 10 healthcare professionals to assess the feasibility. The questionnaire was then modified slightly to improve clarity and comprehensibility, such as adding a note “can select multiple answers” for each multiple-choice question and summarizing long statements more succinctly without changing the meaning.

The questionnaire comprised 3 sections (see Supplemental Appendix). The first section included demographic information (gender, age group, marital status, educational level) and job-related factors (years of experience in the field, position held, length of service in the hospital, number of concurrent job positions, monthly on-call shifts, and number of direct patient interactions).

The second section comprised 10 questions to evaluate the participant’s knowledge about reporting ADRs, including 7 multiple-choice questions with multiple correct answers and 3 multiple-choice questions with only one correct answer. For the multiple-choice questions with multiple correct answers, a response was considered correct if the number of correct answers met or exceeded half of the total correct answers. Each correct answer received 1 point and incorrect answers received 0 points, resulting in a total knowledge score ranging from 0 to 10.

Attitudes toward ADR reporting were assessed through 9 questions each using a 5-point Likert scale ranging from 1 (strongly disagree) to 5 (strongly agree). One of the questions was negatively worded and was scored in reverse. For each attitude question, responses of 4 and 5 were classified as positive, while responses of 1 and 2 were classified as negative. The total attitude score was calculated by summing the scores for all attitude questions, ranging from 9 to 45.

The knowledge and attitude thresholds were classified based on the average score of the total knowledge and attitude scores of all participants, respectively.^20,44 Individuals with knowledge and attitude scores above this average were considered to have good knowledge and positive attitudes, while those below were considered to have poor knowledge and negative attitudes.

Ethical Approval

This research protocol was approved by the Medical Ethics Council of Can Tho University of Medicine and Pharmacy, Can Tho, Vietnam (reference: 22.015.HV/PCT-HDDD, 25th July 2022). All participants were informed about the voluntary nature of participation in the study.

Statistical Methods

Data were encoded and entered into Epi Info version 3.1 data management software, and statistical analysis was performed using SPSS version 22.0. Descriptive statistics such as frequency (percentage) were used to summarize qualitative data while mean (± standard deviation; SD) was used for quantitative data. The Chi-squared test was used to examine differences associated with categorical variables. The normal distribution of the continuous variables was examined using the Kolmogorov-Smirnov test, Shapiro-Wilk test, and Q-Q plots. In this study, none of the continuous variables exhibited a normal distribution. Therefore, the Mann-Whitney test was employed to compare the differences in mean scores of knowledge and attitudes among professional groups categorized by age group, years of experience in the field, and healthcare profession. Univariate and multivariate logistic regression models were used to identify factors associated with knowledge and attitudes toward ADR reporting. Variables found to be significant in the univariate logistic regression were included in the multivariate regression. ⁴⁵ The adequacy of the sample size for multiple logistic regression analysis was determined based on the proposal by Peduzzi et al. ⁴⁶ Significance was considered at a threshold of P < .05.

Results

This study recruited 511 healthcare professionals, with a response rate of 92.9%, where 63.8% were women (Table 1). The majority of participants were aged 30 to 40 years (37.6%) and were married (69.3%). Most of the healthcare professionals had a university degree (52.3%) and were working in a nursing role (49.1%). A large proportion of the participants had more than 5 years’ experience in the field (73.6%) and held permanent/long-term contract staff positions (83.3%). Additionally, 70.3% of the participants had worked in the hospital for more than 5 years, and the majority held only one job position (80.4%). The number of direct patient interactions varied, with 41.6% reporting more than 20 interactions per day. The majority of participants reported more than 2 monthly on-call shifts (79.8%). Regarding reporting ADRs, 62.4% of healthcare professionals had good knowledge, but only 53.6% had a positive attitude toward reporting ADRs.

Table 1.

Characteristics of Respondents (n = 511).

Characteristics		Overall N (%)	Pharmacist (n = 36)	Medical practitioner (n = 140)	Nurse (n = 251)	Other (n = 84)	P value*
Gender	Men	185 (36.2)	11 (30.6)	74 (52.9)	79 (31.5)	21 (25)	<.001
	Women	326 (63.8)	25 (69.4)	66 (47.1)	172 (68.5)	63 (75)
Age group (years)	<30	130 (25.4)	5 (13.9)	56 (40)	56 (22.3)	13 (15.5)	<.001
	30-40	192 (37.6)	18 (50)	39 (27.9)	109 (43.4)	26 (31)
	>40	189 (37)	13 (36.1)	45 (32.1)	86 (34.3)	45 (53.6)
Marital status	Single	157 (30.7)	8 (22.2)	67 (47.9)	67 (26.7)	15 (17.9)	<.001
	Married	354 (69.3)	28 (77.8)	73 (52.1)	184 (73.3)	69 (82.1)
Educational level	Intermediate degree	100 (19.6)	5 (13.9)	1 (0.7)	74 (29.5)	20 (23.8)	<.001**
	College degree	83 (16.2)	13 (36.1)	1 (0.7)	54 (21.5)	15 (17.9)
	University degree	267 (52.3)	12 (33.3)	91 (65)	116 (46.2)	48 (57.1)
	Master’s degree/Specialist degree I	43 (8.4)	6 (16.7)	37 (26.4)	0 (0)	0 (0)
	Doctorate degree/Specialist degree II	18 (3.5)	0 (0)	10 (7.1)	7 (2.8)	1 (1.2)
Years of experience in the field (years)	<1	15 (2.9)	0 (0)	14 (10)	1 (0.4)	0 (0)	<.001**
	1-5	120 (23.5)	7 (19.4)	59 (42.1)	46 (18.3)	8 (9.5)
	>5	376 (73.6)	29 (80.6)	67 (47.9)	204 (81.3)	76 (90.5)
Position	Head of department	13 (2.5)	3 (8.3)	8 (5.7)	1 (0.4)	1 (1.2)	<.001**
	Deputy head of department	13 (2.5)	1 (2.8)	12 (8.6)	0 (0)	0 (0)
	Permanent/long-term contract staff	425 (83.3)	32 (88.9)	87 (62.1)	228 (90.8)	78 (92.9)
	Short-term contract staff	60 (11.7)	0 (0)	33 (23.6)	22 (8.8)	5 (6)
Length of service in the hospital (years)	<1	18 (3.5)	1 (2.8)	15 (10.7)	2 (0.8)	0 (0)	<.001**
	1-5	134 (26.2)	10 (27.8)	64 (45.7)	48 (19.1)	12 (14.3)
	>5	359 (70.3)	25 (69.4)	61 (43.6)	201 (80.1)	72 (85.7)
Number of concurrent job positions	0	411 (80.4)	20 (55.6)	115 (82.1)	204 (81.3)	72 (85.7)	.009
	1	55 (10.8)	8 (22.2)	13 (9.3)	26 (10.4)	8 (9.5)
	≥2	45 (8.8)	8 (22.2)	12 (8.6)	21 (8.4)	4 (4.8)
Monthly on-call shifts	0	93 (18.2)	21 (58.3)	26 (18.6)	26 (10.4)	20 (23.8)	<.001**
	1-2	10 (2)	4 (11.1)	0 (0)	6 (2.4)	0 (0)
	>2	408 (79.8)	11 (30.6)	114 (81.4)	219 (87.3)	64 (76.2)
Number of direct patient interactions	<10	103 (20.2)	23 (63.9)	12 (8.6)	49 (19.5)	19 (22.6)	<.001
	10-20	195 (38.2)	3 (8.3)	50 (35.7)	131 (52.2)	11 (13.1)
	>20	213 (41.6)	10 (27.8)	78 (55.7)	71 (28.3)	54 (64.3)
Knowledge about reporting ADRs	Good	319 (62.4)	15 (41.7)	101 (72.1)	162 (64.5)	41 (48.8)	<.001
	Poor	192 (37.6)	21 (58.3)	39 (27.9)	89 (35.5)	43 (51.2)
Attitude toward reporting ADRs	Positive	274 (53.6)	9 (25)	82 (58.6)	135 (53.8)	48 (57.1)	.003
	Negative	237 (46.4)	27 (75)	58 (41.4)	116 (46.2)	36 (42.9)

Note. Categorical variables are reported as numbers (%). *Chi-squared test and **Fisher’s Exact Test was used for categorical data analysis.

Bold entries indicate statistically significant differences.

Over 90% of participants demonstrated an understanding of the importance of reporting ADRs even if they have already been recorded by the drug manufacturer (Table 2). Additionally, more than three-quarters of participants knew how to submit an ADR report to the National or Regional Center for DI & ADR Monitoring (75.7%) and could successfully identify the individual responsible for composing the ADR report (80.6%). However, only 51.1% of the participants correctly identified the location of the National Center for DI & ADR Monitoring, and only 44.6% of participants could identify where to obtain the ADR report form. When comparing the different professional groups, pharmacists had a significantly lower rate of correct responses compared to both medical practitioners and nurses on various issues, including types of ADR that should be reported (P < .001), types of pharmaceutical products that should be reported in an ADR (P < .001), the minimum information required in the ADR report form (P < .001), the methods of submitting the ADR report to the National or Regional Center for DI & ADR Monitoring (P = .003), and the role of reporting ADRs in professional practice (P = .014).

Table 2.

Knowledge About Reporting ADRs (n = 511).

Items †	Total correct responses (n = 511)	Pharmacist (n = 36)	Medical practitioner (n = 140)	Nurse (n = 251)	Other (n = 84)	P value*
Types of ADR that should be reported	326 (63.8)	16 (44.4)	97 (69.3)	176 (70.1)	37 (44)	<.001
Types of pharmaceutical products that are appropriate to report	324 (63.4)	9 (25)	90 (64.3)	165 (65.7)	60 (71.4)	<.001
The individual(s) directly responsible for writing the ADR report	412 (80.6)	26 (72.2)	121 (86.4)	195 (77.7)	70 (83.3)	.093
The minimum information needed on the ADR report form	371 (72.6)	21 (58.3)	108 (77.1)	203 (80.9)	39 (46.4)	<.001
The location of the National Center for Drug Information and ADR Monitoring	261 (51.1)	29 (80.6)	70 (50)	97 (38.6)	65 (77.4)	<.001
The methods of submitting the ADR report to the National or Regional Center for Drug Information and ADR Monitoring	387 (75.7)	26 (72.2)	120 (85.7)	187 (74.5)	54 (64.3)	.003
The source for obtaining the ADR report form	228 (44.6)	14 (38.9)	74 (52.9)	107 (42.6)	33 (39.3)	.128
Understanding the necessity to report ADRs even though they have already been recorded by the manufacturer	465 (91)	23 (63.9)	127 (90.7)	235 (93.6)	80 (95.2)	<.001
The legal document regulates and issues the ADR reporting form	305 (59.7)	23 (63.9)	93 (66.4)	132 (52.6)	57 (67.9)	.015
The role of reporting ADRs in professional practice	381 (74.6)	24 (66.7)	114 (81.4)	190 (75.7)	53 (63.1)	.014

^†Categorical variables are reported as frequency (%).

^*Chi-squared test was used for categorical data analysis.

Bold entries indicate statistically significant differences.

Regarding attitudes toward reporting ADRs (Table 3), more than 85% of the participants believed that ADR reporting is necessary (92%), ADR reporting has a positive impact on the healthcare system (85.7%) and expressed a willingness to undertake ADR reporting training (85.5%). However, only 37.6% of the participants expressed confidence in performing ADR reporting effectively. When comparing the different professional groups, the majority of pharmacists had fewer significant positive responses regarding issues such as the necessity of reporting all suspected ADRs (P < .001) and considering ADR reporting as an important aspect of professional practice (P = .035), than did medical practitioners and nurses.

Table 3.

Attitude Toward Reporting ADRs (n = 511).

Items †	Strongly disagree	Disagree	Neutral	Agree	Strongly agree	Total positive responses (n = 511)	Pharmacist (n = 36)	Medical practitioner (n = 140)	Nurse (n = 251)	Other (n = 84)	P value*
Willingness to implement ADR reporting in practice	6 (1.2)	19 (3.7)	73 (14.3)	204 (39.9)	209 (40.9)	413 (80.8)	35 (97.2)	113 (80.7)	186 (74.1)	79 (94)	.001
ADR reporting is necessary	7 (1.4)	14 (2.7)	20 (3.9)	178 (34.8)	292 (57.1)	470 (92)	34 (94.4)	128 (91.4)	225 (89.6)	83 (98.8)	.062**
All suspected ADRs need to be reported	13 (2.5)	15 (2.9)	123 (24.1)	132 (25.8)	228 (44.6)	360 (70.5)	18 (50)	108 (77.1)	161 (64.1)	73 (86.9)	<.001
ADR reporting is an important part of professional work	5 (1)	6 (1.2)	73 (14.3)	168 (32.9)	259 (50.7)	427 (83.6)	26 (72.2)	119 (85)	204 (81.3)	78 (92.9)	.035**
The benefits of ADR reporting are to identify and detect new ADRs of drugs	6 (1.2)	11 (2.2)	54 (10.6)	191 (37.4)	249 (48.7)	440 (86.1)	31 (86.1)	121 (86.4)	208 (82.9)	80 (95.2)	.036**
ADR reporting has a positive impact on the healthcare system	8 (1.6)	8 (1.6)	57 (11.2)	211 (41.3)	227 (44.4)	438 (85.7)	31 (86.1)	122 (87.1)	205 (81.7)	80 (95.2)	.002**
Willingness to participate in ADR reporting training programs	3 (0.6)	8 (1.6)	63 (12.3)	188 (36.8)	249 (48.7)	437 (85.5)	34 (94.4)	118 (84.3)	207 (82.5)	78 (92.9)	.067**
Confident in performing ADR reporting well	68 (13.3)	69 (13.5)	182 (35.6)	103 (20.2)	89 (17.4)	192 (37.6)	14 (38.9)	55 (39.3)	101 (40.2)	22 (26.2)	.001
Reporting ADRs is not necessary because of the potential impact on patient information security ‡	225 (44)	83 (16.2)	98 (19.2)	61 (11.9)	44 (8.6)	308 (60.3)	21 (58.3)	95 (67.9)	152 (60.6)	40 (47.6)	<.001

^†Categorical variables are reported as frequency (%). ^‡The question was worded negatively and scored in reverse, thus responses of “Strongly Disagree” and “Disagree” were interpreted as positive. ^*The Chi-squared test and ^**Fisher’s Exact Test were used for the categorical data analysis between the attitude variables (with 3 response types: positive, neutral, and negative) and the professions of the health care professionals (pharmacist, medical practitioner, nurse, and other).

Bold entries indicate statistically significant differences.

Figure 1 illustrates significant differences in knowledge scores based on age group (P = .004) and years of experience in the field (P < .001). Additionally, significant differences in knowledge scores were observed based on healthcare profession between pharmacists and medical practitioners (P = .002), as well as between pharmacists and nurses (P = .035). The mean (±SD) knowledge score of pharmacists (5.86 ± 2.59) was significantly lower than that of medical practitioners (7.24 ± 1.96), and nurses (6.72 ± 2.09). Concerning attitudes, significant differences were found to be associated with age group (P = .043), and with healthcare profession between pharmacists and medical practitioners (P = .002) and between pharmacists and nurses (P = .008). Pharmacists (34.61 ± 3.24) scored significantly lower than medical practitioners (37.21 ± 6.68) and nurses (36.86 ± 5.97). However, no significant differences were found to be associated with years of experience in the field (P = .180).

Figure 1.

Differences in knowledge scores (A) and attitudes (B) toward ADR reporting, distributed by age group, years of experience in the field, and healthcare profession, using the Mann-Whitney Test. The abbreviation Pab represents the P-value for the difference between group a (pharmacist) and group b (medical practitioner).

The results of the multivariate analysis of factors associated with poor knowledge of ADR reporting among healthcare workers are presented in Table 4. The sample size used for this regression model is deemed appropriate as it exceeds the recommendation of Peduzzi et al, who suggest a minimum of 10 × 8/0.376, resulting in 213 minimum subjects. Participants with a intermediate/college degree had poorer knowledge of ADR reporting compared to those with a university degree (aOR = 0.521, 95% CI: 0.336-0.809, P = .004). Pharmacists had poorer knowledge of ADR reporting compared to medical practitioners (aOR = 0.316, 95% CI: 0.125-0.801, P = .015) and nurses (aOR = 0.325, 95% CI: 0.14-0.755, P = .009). Furthermore, this study revealed that the absence of monthly on-call shifts (aOR = 2.245, 95% CI: 1.249-4.035, P = .007) and having >20 direct patient interactions (aOR = 3.275, 95% CI: 1.718-6.243, P < .001) were associated with poorer knowledge of ADR reporting.

Table 4.

Factors Associated With Poor Knowledge of ADR Reporting Among Healthcare Workers (n = 511).

Characteristics		Knowledge †		Univariate			Multivariate
		Poor	Good	OR	95% CI	P value	OR	95% CI	P value
Gender
Men	185 (36.2)	68 (36.8)	117 (63.2)	1	-	-
Women	326 (63.8)	124 (38.0)	202 (62.0)	1.056	0.727-1.534	.774
Age group (years)
≤40	322 (63.0)	103 (32.0)	219 (68.0)	1	-	-	1	-	-
>40	189 (37.0)	89 (47.1)	100 (52.9)	1.892	1.308-2.738	.001	1.367	0.877-2.13	.168
Marital status
Single	157 (30.7)	51 (32.5)	106 (67.5)	1	-	-
Married	354 (69.3)	141 (39.8)	213 (60.2)	1.376	0.926-2.044	.114
Educational level
Intermediate/College degree	183 (35.8)	88 (48.1)	95 (51.9)	1	-	-	1	-	-
University degree	267 (52.3)	81 (30.3)	186 (69.7)	0.470	0.318-0.694	<.001	0.521	0.336-0.809	.004
Postgraduate	61 (11.9)	23 (37.7)	38 (62.3)	0.653	0.361-1.183	.160	0.502	0.226-1.115	.090
Health care professional’s profession
Pharmacist	36 (7.0)	21 (58.3)	15 (41.7)	1	-	-	1	-	-
Medical practitioner	140 (27.5)	39 (27.9)	101 (72.1)	0.276	0.129-0.589	.001	0.316	0.125-0.801	.015
Nurse	251 (49.1)	89 (35.5)	162 (64.5)	0.392	0.193-0.799	.010	0.325	0.14-0.755	.009
Other	84 (16.4)	43 (51.2)	41 (48.8)	0.749	0.340-1.648	.473	0.567	0.229-1.403	.220
Years of experience in the field (years)
≤5	135 (26.4)	31 (23.0)	104 (77.0)	1	-	-	1	-	-
>5	376 (73.6)	161 (42.8)	215 (57.2)	2.512	1.602-3.940	<.001	1.438	0.474-4.363	.521
Position
Permanent/long-term contract staff	451 (88.3)	180 (39.9)	271 (60.1)	2.657	1.373-5.141	.004	1.518	0.69-3.341	.300
Short-term contract staff	60 (11.7)	12 (20.0)	48 (80.0)	1	-	-	1	-	-
Length of service in the hospital (years)
≤5	152 (29.7)	39 (25.7)	113 (74.3)	1	-	-	1	-	-
>5	359 (70.3)	153 (42.6)	206 (57.4)	2.152	1.414-3.275	<.001	1.111	0.403-3.063	.838
Number of concurrent job positions
0	411 (80.4)	154 (37.5)	257 (62.5)	1	-	-
1	55 (10.8)	19 (34.5)	36 (65.5)	0.881	0.488-1.590	.674
≥2	45 (8.8)	19 (42.2)	26 (57.8)	1.220	0.653-2.277	.533
Monthly on-call shifts
No	93 (18.2)	46 (49.5)	47 (50.5)	1.823	1.159-2.870	.009	2.245	1.249-4.035	.007
Yes	418 (81.8)	146 (34.9)	272 (65.1)	1	-	-	1	-	-
Number of direct patient interactions
<10	103 (20.2)	31 (30.1)	72 (69.9)	1	-	-	1	-	-
10-20	195 (38.2)	70 (35.9)	125 (64.1)	1.301	0.779-2.172	.315	3.033	1.561-5.892	.001
>20	213 (41.6)	91 (42.7)	122 (57.3)	1.732	1.050-2.859	.032	3.275	1.718-6.243	<.001

^†Categorical variables are reported as frequency (%).

Bold entries indicate statistically significant differences.

Table 5 shows the factors associated with negative attitudes toward ADR reporting among healthcare workers as obtained in the multivariate analysis. The sample size used for this regression model is deemed appropriate as it exceeds the recommendation of Peduzzi et al, who suggest a minimum of 10 × 3/0.464, resulting in 65 minimum subjects (adjusted to ensure a minimum sample size of 100). Participants aged 40 or younger had a more negative attitude toward ADR reporting than others (aOR = 1.660, 95% CI: 1.139-2.421, P = .008). Pharmacists had a more negative attitude toward ADR reporting compared to doctors (aOR = 0.254, 95% CI: 0.107-0.607, P = .002) and nurses (aOR = 0.327, 95% CI: 0.142-0.749, P = .008).

Table 5.

Factors Associated With Negative Attitudes Toward ADR Reporting Among Healthcare Professionals (n = 511).

Characteristics		Attitude †		Univariate			Multivariate
		Negative	Positive	OR	95% CI	P value	OR	95% CI	P value
Gender
Men	185 (36.2)	88 (47.6)	97 (52.4)	1	-	-
Women	326 (63.8)	149 (45.7)	177 (54.3)	0.928	0.646-1.332	.685
Age group (years)
≤40	322 (63.0)	163 (50.6)	159 (49.4)	1.593	1.106-2.294	.012	1.660	1.139-2.421	.008
>40	189 (37.0)	74 (39.2)	115 (60.8)	1		-	1	-	-
Marital status
Single	157 (30.7)	72 (45.9)	85 (54.1)	1	-	-
Married	354 (69.3)	165 (46.6)	189 (53.4)	1.031	0.707-1.503	.875
Educational level
Intermediate/College degree	183 (35.8)	88 (48.1)	95 (51.9)	1	-	-
University degree	267 (52.3)	127 (47.6)	140 (52.4)	0.979	0.672-1.427	.913
Postgraduate	61 (11.9)	22 (36.1)	39 (63.9)	0.609	0.335-1.107	.104
Health care professional’s profession
Pharmacist	36 (7.0)	27 (75.0)	9 (25.0)	1	-	-	1	-	-
Medical practitioner	140 (27.5)	58 (41.4)	82 (58.6)	0.236	0.103-0.539	.001	0.254	0.107-0.607	.002
Nurse	251 (49.1)	116 (46.2)	135 (53.8)	0.286	0.129-0.634	.002	0.327	0.142-0.749	.008
Other	84 (16.4)	36 (42.9)	48 (57.1)	0.250	0.105-0.596	.002	0.279	0.113-0.685	.005
Years of experience in the field (years)
≤5	135 (26.4)	60 (44.4)	75 (55.6)	1	-	-
>5	376 (73.6)	177 (47.1)	199 (52.9)	1.112	0.749-1.651	.599
Position
Permanent/long-term contract staff	451 (88.3)	214 (47.5)	237 (52.5)	1	-	-
Short-term contract staff	60 (11.7)	23 (38.3)	37 (61.7)	0.688	0.396-1.196	.185
Length of service in the hospital (years)
≤5	152 (29.7)	71 (46.7)	81 (53.3)	1	-	-
>5	359 (70.3)	166 (46.2)	193 (53.8)	0.981	0.671-1.435	.922
Number of concurrent job positions
0	411 (80.4)	187 (45.5)	224 (54.5)	1	-	-
1	55 (10.8)	25 (45.5)	30 (54.5)	0.998	0.567-1.757	.995
≥2	45 (8.8)	25 (55.6)	20 (44.4)	1.497	0.806-2.781	.201
Monthly on-call shifts
No	93 (18.2)	50 (53.8)	43 (46.2)	1	-	-
Yes	418 (81.8)	187 (44.7)	231 (55.3)	0.696	0.443-1.093	.115
Number of direct patient interactions
<10	103 (20.2)	56 (54.4)	47 (45.6)	1	-	-	1	-	-
10-20	195 (38.2)	81 (41.5)	114 (58.5)	0.596	0.369-0.965	.035	0.697	0.414-0.174	.175
>20	213 (41.6)	100 (46.9)	113 (53.1)	0.743	0.463-1.191	.217	0.938	0.564-1.564	.805

^†Categorical variables are reported as frequency (%).

Bold entries indicate statistically significant differences.

Discussion

The present study found that only 51.1% of participants were able to correctly identify the location of the National Center for Drug Information and ADR Monitoring, and only 44.6% of participants knew where to obtain the ADR report form. These findings are similar to those of studies conducted worldwide.^47-49 The ADR reporting rate in the studied hospital setting was found to be very low compared to that of other provinces in Vietnam. ¹⁶ The lack of knowledge about ADR reporting may be one of the reasons for this low reporting rate. ⁴⁷ Regarding factors affecting knowledge about ADR reporting, our study found that participants with a intermediate/college degree had poorer knowledge of ADR reporting compared to those with a university degree (P = .004). This may be due to university education providing more in-depth knowledge than intermediate/college education. ⁵⁰ Therefore, hospitals need to focus on improving the knowledge of staff who have not completed university-level education.

In Vietnam, the role of the pharmacist in ADR reporting is regulated by legislation such as Circular No. 23/2011/TT-BYT, which states that the Pharmacy Department is responsible for reporting adverse drug reactions to the hospital management and sending them to the National Center for Drug Information and ADR Monitoring immediately after processing. ⁵¹ According to 2022 national data in Vietnam, pharmacists are the most common reporters of ADRs. ¹⁶ Although the role of pharmacists in national pharmacovigilance systems may vary worldwide, it is widely recognized that reporting ADRs is an important part of their professional responsibility and that they have a positive attitude toward ADR reporting. ⁵² However, many studies have shown that there are still significant gaps in pharmacists’ knowledge around ADR reporting, particularly in countries where their role in healthcare is limited.^48,49,53 Our study also found that pharmacists had poorer knowledge of ADR reporting compared to medical practitioners (P = .015) and nurses (P = .009), in agreement with findings from the Philippines ⁵⁴ and Jordan. ⁴⁷ Pharmacists’ lack of knowledge around ADR reporting may be due to their multiple job responsibilities and limited patient contact in clinical settings. ⁵⁴ One study found that the main barrier to ADR reporting among pharmacists was the lack of time spent in clinical practice. ⁵⁵ Conversely, doctors and nurses often have more patient contact and spend longer monitoring and discussing symptoms, resulting in a higher level of knowledge around ADR reporting. ⁵⁴ The study results support the suggestion that dedicated efforts are needed to enhance ADR reporting among pharmacists. One recommendation that can be derived from the data is to improve the proactive activities of the clinical pharmacy team within the pharmacy department of the studied hospital setting, where a designated pharmacist would conduct rounds in the hospital to identify and report ADRs. Implementing such an approach can significantly contribute to strengthening the ADR reporting system. Furthermore, to ensure the effective implementation of this reporting, expanding the education program to the entire hospital ensures that all healthcare professionals throughout the hospital are equipped with the necessary knowledge and competencies to effectively identify, report, and manage ADRs.

Regarding healthcare workers’ attitudes toward ADR reporting, the present study found that 92% of healthcare workers acknowledged ADR reporting is necessary and 83.6% believed ADR reporting to be an important part of their professional role, in agreement with the findings of many studies worldwide.^11,40,56,57 Among healthcare workers, nurses had the lowest positive response to ADR reporting being necessary, at 89.6%, and nurses were also the least willing to implement ADR reporting in practice (74.1%). Therefore, educational interventions should focus on nurses. Exchanging and participating in training programs may help to eliminate misconceptions and modify attitudes toward ADR reporting.^58,59

Our study found that only 37.6% of healthcare workers were confident they were performing ADR reporting well. This may be due to a lack of knowledge, lack of information about drugs, lack of financial support, and fear of responsibility.^13,40,57,60 However, our results showed that up to 85.5% of healthcare workers were willing to undertake training in ADR reporting. These data show that healthcare workers need more training on ADR reporting, this will emphasize the importance of ADR reporting for patient safety in particular and the healthcare system in general. During market circulation, the safety of drugs needs to be regularly evaluated to identify potential risks, the time at which treatment is most effective, and to reassess the risk-benefit balance. Early detection and reporting of ADRs by healthcare workers will provide more complete and accurate information on the safe use of drugs. Among the healthcare roles surveyed, nurses were the least willing to undertake ADR reporting training (82.5%), indicating that solutions need to focus on this group, as nurses may often be the first to notice the symptoms of an ADR in the hospital setting and thus play an important role in monitoring ADRs in patients. ⁶¹

Although guidelines worldwide encourage reporting of all ADRs including known, unknown, common, uncommon, serious, or mild, even including reactions to established medicines, ⁴⁰ only 70.5% of healthcare workers in our study agreed with the statement that all suspected ADRs need to be reported. Another study in Vietnam showed that few healthcare workers were interested in new ADRs and serious ADRs (52.7% and 56.3%, respectively), although these are priority ADRs for voluntary reporting systems. ⁶² In particular, the ADR reporting rate described in the literature was very low (24.2%), possibly because most healthcare workers considered these ADRs too common to report. ⁶²

The availability of drug information has significantly improved for healthcare professionals in recent years. With the advancements in technology and the widespread use of the internet, healthcare professionals now have easier access to a wealth of drug-related information. Younger healthcare professionals tended to access online databases (such as Cochrane Library, MEDLINE, UpToDate, etc.) more frequently than their older colleagues, possibly due to their familiarity with new technologies. ⁶³ This could contribute to reported observations of younger individuals tending to have higher knowledge compared to their older counterparts, which in turn aligns with our findings that healthcare professionals aged 40 and below had significantly higher knowledge scores than those over 40 years of age.

Attitude is a driving force behind ADR reporting, and thus a positive attitude can encourage timely ADR reporting.^52,64 Our study found that participants aged 40 or younger were more negative toward ADR reporting compared to those over 40 years old (P = .008). This could be due to older healthcare workers having more experience with ADR cases, and thus a better understanding of the harm ADRs can cause to patients, in addition to having undertaken more training in ADR than their younger counterparts. ⁵² Additionally, pharmacists were more negative toward ADR reporting than were doctors (P = .002) or nurses (P = .008). ⁴⁷ It has been reported that many pharmacists feel that ADR reporting adds to their workload and is time-consuming. ⁶⁴ Therefore, interventions working to improve the attitudes of pharmacists are needed to increase the ADR reporting rate.

Our study did not find a correlation between experience and attitude, in contradiction to a study by Adisa and Omitogun, who reported that healthcare workers with ≤1 to 5 years of experience practicing demonstrated a significantly more positive attitude toward ADR reporting compared to those with >5 years of experience. ²² However, a significant correlation between experience and knowledge was discovered in the current study, indicating that individuals with more than 5 years of experience had lower knowledge scores. This suggests the need for appropriate measures to update the knowledge of these individuals.

Currently, the role of the pharmacist has changed worldwide, from simply a dispenser to a guardian of drug safety. Several studies have shown that hospital pharmacists play an important role in detecting and reporting ADRs and preventing related incidents.^52,65 Additionally, pharmacists possess clinical knowledge, and their exchanges with physicians and patients can promote a better understanding of suspected ADRs. This study suggests the need for training and education on ADR reporting, particularly for pharmacists, as well as for those with intermediate/college education levels. Encouraging participation in continuous professional development programs, seminars, workshops, and post-training reminders, along with promoting hospital clinical pharmacy practice, can effectively enhance healthcare professionals’ knowledge in this area.^{40,44,61,65-67} Educational strategies have been demonstrated to improve and increase ADR reporting.^40,61 Furthermore, teaching pharmacy at different levels is necessary to establish a theoretical and practical knowledge base for future generations while still in school.^52,65 In addition, a positive attitude toward ADR reporting is important and has a positive impact on the ADR reporting practices of healthcare workers.^44,52 To improve attitudes, education-based interventions listed may be useful in eliminating misconceptions and correcting attitudes toward ADR reporting. Moreover, financial incentives may also be meaningful in improving the attitudes of ADR reporters.^44,61,65,66 Financial incentives can be effective in motivating healthcare professionals to report ADRs. For example, a study by Bäckström and Mjörndal demonstrated that providing a small financial incentive, such as 2 lottery tickets, led to an increase in reported ADRs. ⁶⁸ In addition, Chang et al discovered that offering a fixed financial incentive in the form of a 20 RMB bonus for spontaneously reporting ADRs (which constituted less than 1% of the physician’s salary) effectively motivated ADR reporting. ⁶⁹ However, future studies in Vietnam are necessary to confirm the effectiveness and sustainability of financial incentives.

In Vietnam, ADR reporting does not follow an anonymous process, as specified by Circular No. 23/2011/TT-BYT, as it requires both patient and reporter information to be included in the data collection form. The non-anonymous reporting requirement can be perceived as a barrier by healthcare professionals. For example, a study by Agarwal et al found that more than one-third of the participants expressed concerns about the confidentiality of the patient and their own identity. ²¹ Additionally, a previous study by Elkalmi et al involving community pharmacists highlighted concerns regarding potential legal actions despite the non-anonymous reporting system. These findings emphasize the need for a comprehensive assessment of the impact and potential drawbacks of non-anonymous reporting systems in ADR in future studies. ⁷⁰

The study results suggest a possible correlation between poor knowledge and negative attitudes and healthcare profession. This finding may explain the significant impact of clinical-based care on reporting ADRs due to its influence on the knowledge and attitudes of healthcare professionals. It is noteworthy that many pharmacists in this study were less directly involved in patient bedside care. From this perspective, it is crucial to emphasize the importance of clinic-based care in improving ADR reporting. Active participation in patient care provides healthcare professionals, including pharmacists, with more opportunities to identify and report ADRs promptly. Direct patient interaction enables close monitoring and discussion of symptoms, resulting in a better understanding of ADRs and their reporting. Therefore, promoting a clinic-based approach and ensuring active involvement in patient care can significantly enhance ADR reporting activities and contribute to improving patient safety. Additionally, organizing information-sharing meetings among experts and disseminating the findings from previous ADR reports can further enhance the effectiveness of the current research site. By facilitating the exchange of information and experiences between healthcare professionals and sharing the outcomes derived from real-world ADR reporting data, valuable insights can be gained to supplement the knowledge and attitudes of healthcare professionals. This collaborative approach promotes continuous learning and improvement in the field of ADR reporting.

Limitations

The study had some limitations. First, the study population included only healthcare workers in a single public hospital in a specific province in Vietnam, thus the findings may not be representative of the entire population of Vietnam or be generalizable to any other nation. Second, evaluating knowledge of ADR reporting through a questionnaire may not be comprehensive and may not accurately reflect the full extent of healthcare workers’ knowledge. However, incorporating different aspects of measuring knowledge based on previous studies may reduce design-related biases. Third, the study relied on self-reported data, which may be subject to biases related to recall and to social desirability. The present study was conducted anonymously to reduce the impact of social pressure on respondents. Fourth, the study only examined demographic and job-related factors influencing knowledge and attitudes toward ADR reporting and did not explore other potential factors such as organizational culture and workload. Fifth, there is a lack of specific data regarding the distribution of healthcare professionals among different departments. The questionnaire design did not include a variable related to department type, hence leaving a gap in our investigation. This may have influenced the overall understanding and interpretation of our findings. Future studies should consider incorporating this aspect for a more comprehensive view of the attitudes and knowledge regarding ADRs. Additionally, the study did not investigate the impact of ADR reporting on patient outcomes, healthcare quality, and safety. Future research should address these limitations to provide a more comprehensive understanding of ADR reporting behavior among healthcare professionals and inform strategies to improve ADR reporting practices in healthcare settings. Finally, some aspects were overlooked in this study, such as the motivations to submit ADRs, and barriers, particularly concerns related to legal liability. Further qualitative research is needed to address these gaps in the future.

Conclusions

This study identified several factors associated with lower levels of knowledge and negative attitudes toward ADR reporting among healthcare workers. Having a intermediate/college degree, being a pharmacist, not having monthly on-call shifts, and having fewer than 20 direct patient interactions were associated with lower levels of knowledge regarding ADR reporting. Meanwhile, being younger (≤40 years) and being a pharmacist were identified as factors associated with negative attitudes toward ADR reporting. These findings highlight the need for targeted interventions and education programs to improve healthcare workers’ knowledge and attitudes toward ADR reporting.