Abstract
Aims
Clinical trials (CTs) are critical to advancing of patient care. Understanding the public’s knowledge and the attitudes toward participating in CTs is important for their successful implication. In Jordan this data is currently not available. The present study aimed to explore the knowledge, attitude and perception of Jordanians toward CTs participation.
Methods
A cross-sectional study was conducted on 1216 Jordanians recruited from public hospitals and pharmaceutical research centers.
Results
About 20.5% of the respondents have previously participated in a CT. About 68.3% and 50.1% had good knowledge and positive attitude toward CTs respectively. Good knowledge was associated with male gender (OR = 1.696, 95% CI = 1.284–2.240, p<0.001), higher education (OR = 1.433, 95% CI =1.107–1.856, p = 0.006) and healthy condition (OR = 1.822, 95% CI = 1.234–2.690, p=0.003); while older age was associated with a poor knowledge (OR = 0.985, 95% CI = 0.972–0.998, p=0.026). Female gender (OR = 1.817, 95% CI = 1.406 – 2.349, p<0.001), higher education (OR = 1.294, 95% CI = 1.017 – 1.646, p=0.036) and previous participation (OR = 1.919, 95% CI = 1.388 – 2.653, p<0.001) were factors predicting positive attitudes. A very weak positive correlation was found between knowledge and attitude ( Spearman’s r = 0.074, p =0.01). Regarding perceptions, most of the respondents (85.3%) perceive that CTs are conducted in an ethical manner in Jordan, only 52.9% however feel comfortable toward participation. A moderate positive correlation was found between knowledge and perception ( Spearman’s r = 0.275, p < 0.001). Taking part in a CT significantly affects knowledge, attitudes and perceptions.
Conclusions
This study revealed important insights regarding knowledge, attitudes and perception of Jordanians toward CTs. Educational interventions can improve awareness of the ethical standards under which CTs are conducted affecting perception to participate. Promotion of clinical trials among patients and healthy individuals is needed to increase participation.
Keywords: Clinical trial, knowledge, attitude, perception, participants, Jordanians
Introduction
Clinical trials (CTs) are considered the gold standard research methodology for rigorously evaluating the effectiveness of healthcare interventions 1. Despite its large population, clinical trial in the Middle East and North Africa (MENA) regions remains under-developed, accounting for less than 1% of all the global clinical trial sites 2. In Jordan, one of the MENA countries, clinical trials started to gain recognition in the early 2000s 3, 4. A decade later, Jordan was recognized as an important research site in the area and the Jordanian healthcare systems are ready to be more involved in CTs 3, 4.
Failure of participants’ recruitment is a long-standing problem and the major challenge toward the successful conduct of clinical research worldwide. Evidence shows that more than two third of CTs fail to recruit the desired number of participants in developed countries 5–7. Lack of knowledge, concerns about clinical trials and the consent procedure, as well as lack of motivation, are generally identified as barriers for conducting CTs 8–10. Fundamental to participant’s participation is the understanding of the basic principles guiding the conduction of clinical trials under an ethical umbrella 9, 10.
Understanding the public’s knowledge and attitudes toward CTs participation and identification of the factors influencing them is important for the successful implication of clinical studies 11. Little is known about knowledge of the MENA region’s populations regarding CTs and surveys of attitudes toward participation are limited 12. In Jordan, no data is currently available. What do Jordanians know about CTs and what might encourage them to take part in a CT? How do they perceive trial participation? Which factors affect their knowledge and attitudes toward participation? The current study aimed to answer the above questions by assessing knowledge, attitudes and perceptions of Jordanians toward CTs participation.
1. Methodology
2.1. Setting and study population
A cross-sectional study was conducted among adult population (age ≥18 years old) in Amman, the capital of Jordan on a total of 1,216 Jordanians. A total of 970 adults visiting the outpatient clinics of two public hospitals (Jordan University Hospital (JUH) and AlNadeem hospital) were invited to participate. In order to compare knowledge, attitudes and perceptions toward clinical trials between respondents that previously participated and those that never participated in a CT, additional 246 participants were recruited from three pharmaceutical research centers in Amman; the Arab Co For Drug Industries & Medical Appliances (ACDIMA) biocenter, the International Pharmaceutical Research Center (IPRC) and the Jordan Center for Pharmaceutical Research (JCPR). Ethical approval was obtained for each institution from the respective Institutional Review Board.
2.2. Data collection
Participants were interviewed by a clinical pharmacist using a modified version of Al-Tannir et al. (2016) questionnaire (Arabic) 13. The questionnaire was divided into four sections. The demographic section included age, gender, educational level, marital status, occupation, history of any chronic disease and previous CT participation. The knowledge section included 17 questions regarding the potential benefit and importance of CTs and the essential components of the informed consent. The responses were scored as correct (score = 1) or incorrect/don’t know (score = 0). The attitudes section included 12 questions regarding factors that might positively affect the participation in a CT. In the perceptions section, 8 questions investigated the feeling of Jordanians toward CTs. The responses for attitude and perception sections were scored as positive (score = 1) or negative (score = 0).
2.3. Data analysis
Data analysis was conducted using SPSS 23.0 software (SPSS Inc., Chicago, IL, USA). Continuous variables were presented as median [interquartile range (IQR)] while categorical variables were presented as frequencies with corresponding percentages.
Knowledge and attitudes were classified into “good knowledge/poor knowledge” and “positive attitude/negative attitude” respectively using 80% as cutoff value: respondents were considered to have “good knowledge” and “positive attitude” if their knowledge and attitude score was equivalent to ≥80% of the respective maximum score 18. Univariate analyses were conducted using Mann–Whitney U test for continuous variables and Chi-square test for categorical variables. Binary logistic regressions were performed to determine factors independently associated with the knowledge (good versus poor) and attitude (positive versus negative). Variables with a p value < 0.2 in the univariate analysis were included in the logistic regression model. Odds ratio (OR) values and their 95% confidence intervals (95% CI) were calculated. The correlations between the knowledge scores and the scores of attitudes and perception were calculated using the Spearman’s correlation coefficient. Statistical significance was set at p value <0.05.
2. Results
3.1. Demographic data
A total of 1,216 Jordanian adults were interviewed, 970 were recruited from outpatient hospital clinics and 246 from pharmaceutical research centers. The demographic characteristics of the respondents are summarized in Table 1. The median age of the study population was 34 years old (IQR 26–45 years) with more than half of them being male (61.8%). Most of the participants was single (60.7%), they were employed (57.4%) and had a bachelor degree (59.8%). Only 16.9% was suffering from chronic diseases. A fifth of the respondents (20.5%), mainly recruited from the pharmaceutical research centers, have previously participated in a CT; all of them were male.
Table 1.
Demographic Characteristics of Respondents (N = 1,216)
| Variablea | Frequency (%) |
|---|---|
| Age (years)b | 34 (18–81) |
| Gender | |
| Male | 752 (61.8) |
| Female | 464 (38.2) |
| Education | |
| School education | 489 (40.2) |
| Bachelor degree | 727 (59.8) |
| Marital status | |
| Single | 738 (60.7) |
| Married | 444 (36.5) |
| Other | 34 (2.8) |
| Occupation | |
| Employed | 98 (57.4) |
| Unemployed | 518 (42.6) |
| Chronic Disease | |
| Yes | 205 (16.9) |
| No | 1011 (83.1) |
| Previous participation | |
| Yes | 249 (20.5) |
| No | 967 (79.5) |
All data expressed as n (%) of participants unless otherwise indicated
Data described as median (Interquartile range)
3.2. Knowledge of Jordanians about clinical trials
The results indicated that 68.3% of the respondents had a good knowledge about clinical trials. The median knowledge score for all the respondents was 14 (IQR 12–15). An overview of the knowledge statements is presented in Table 2. Almost all the respondents (93.1%) knew that “CTs are always necessary to develop a drug and determine its efficacy”. The most recognized ‘improve patient care’ and ‘improve medical knowledge’ as potential benefits arising from CTs (85.7% and 89.9% respectively). More than half (55.3%) of the study population recognized that CTs’ benefits might also expand to ‘improve community wellbeing’ while only 22.6% were aware about the legal protection of volunteers.
Table 2.
Overview of knowledge statements (N= 1,216)
| Statement | Correct answers n (%) |
|---|---|
| CTs are always necessary to develop a drug and determine its efficacy | 1132 (93.1) |
| Potential benefit of CT: improve patient care | 1042 (85.7) |
| Potential benefit of CT: improve medical knowledge | 1093 (89.9) |
| Potential benefit of CT: improve community wellbeing | 673 (55.3) |
| Benefit of CT: no benefit | 3 (0.2) |
| Awareness of the legal protection for participants taking part in CTs | 275 (22.6) |
| Before participation CT study objectives should be clarified* | 1058 (87.0) |
| Participation is voluntary* | 1138 (93.6) |
| Confidentiality of personal information* | 1151 (94.7) |
| Anticipated benefits should be explained* | 1076 (88.6) |
| Foreseeable risks should be explained* | 1068 (87.8) |
| Alternative procedures or courses of treatment should be explained* | 419 (34.5) |
| Any financial compensation should be mentioned* | 862 (70.9) |
| Number of participants should be clarified* | 828 (68.1) |
| The right to withdraw from the study at any time* | 932 (76.6) |
| There are no consequences from the withdrawal* | 902 (74.2) |
| Possibility to ask the researcher for any information at any time* | 1098 (90.3) |
Data are presented as actual numbers (%)
Represent essential elements of the informed consent
Interestingly, even if most of the respondents never participated in a clinical trial, the majority answered correctly most of the questions regarding the essential elements of the informed consent (Table 2).
The univariate analyses showed that age, gender, education, marital status, occupation, the presence of chronic diseases and previous participation were significantly associated with good knowledge of CTs (p <0.05) (Table 3). Respondents that have previously taken part in a CT had a significantly higher median knowledge score (16, IQR 15–17) compared with those that never participated (13, IQR 11–15) (p <0.001).
Table 3.
Univariate and multivariate analysis of factors affecting the participants’ knowledge
| Variablea | Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|---|
| Poor knowledge (386) | Good knowledge (830) | p value | OR (95% CI) | p value | |
| Age (years)b | 38 (18–81) | 32.5 (18–79) | <0.001 | 0.985 (0.972–0.998) | 0.026 |
| Gender | <0.001 | <0.001 | |||
| Female | 185 (47.9) | 279 (33.6) | Ref | ||
| Male | 201 (52.1) | 551 (66.4) | 1.696 (1.284–2.240) | ||
| Education | 0.001 | 0.006 | |||
| School education | 181 (46.9) | 308 (37.1) | Ref | ||
| Bachelor degree | 205 (53.1) | 522 (62.9) | 1.433 (1.107–1.856) | ||
| Marital status | <0.001 | ||||
| Single | 109 (28.2) | 335 (40.4) | Ref | ||
| Married | 260 (67.4) | 478 (57.6) | 0.892 (0.636–1.251) | 0.509 | |
| Other | 17 (4.4) | 17 (2.0) | |||
| Occupation | <0.001 | 0.076 | |||
| Unemployed | 201 (52.1) | 317 (38.2) | Ref | ||
| Employed | 185 (47.9) | 513 (61.8) | 1.288 (0.974–1.705) | ||
| Chronic Disease | <0.001 | 0.003 | |||
| Yes | 106 (27.5) | 99 (11.9) | Ref | ||
| No | 280 (72.5) | 731 (88.1) | 1.822 (1.234–2.690) | ||
| Previous Participation | <0.001 | ||||
| No | 382 (99.0) | 585 (70.5) | _ | ||
| Yes | 4 (1.0) | 245 (29.5) | |||
All data expressed as n (%) of participants unless otherwise indicated
Data described as median (Interquartile range)
Bold values indicate statistical significance p < 0.05
_ Not enough data in the poor knowledge category
The results of the binary logistic regression revealed age, gender, education and chronic diseases as independent factors predicting higher level of knowledge. Male had good knowledge of CTs compared with female (OR = 1.696, 95% CI = 1.284–2.240, p<0.001). In addition, respondents with a higher degree and those without comorbidities were independently associated with good knowledge (OR = 1.433, 95% CI =1.107–1.856, p=0.006) (OR = 1.822, 95% CI = 1.234–2.690, p=0003) respectively. In contrast, older age was associated with poor knowledge compared with younger age (OR = 0.985, 95% CI = 0.972–0.998, p=0.026) (Table 3).
3.3. Attitude of Jordanians towards participating in a clinical trial
In order to understand attitudes of Jordanians toward participation in clinical trials, respondents were asked about factors that might encourage them to take part in a CT.
Half of the respondents (50.1%) had a positive attitude toward participation. The median attitude score of all the respondents was 9 (IQR 7–10). The majority would participate if they: understand the study protocol (98.4%), sign the informed consent (77.1%), receive the best medical care (77%) and receive the results of CT at the end of the study (92.8%). Helping the society (91.7%) and the development of new medications (90.5%) were also reasons encouraging participation for most of the respondents. Only 34.4% and 44.7% were however encouraged to take part in a CT by getting financial compensation and by participation of a family member respectively. An overview of all the attitude statements is presented in Table 4.
Table 4.
Attitudes toward participation in a clinical trial (N = 1,216)
| Statement | Agreed n (%) |
|---|---|
| Factors encouraging participation in clinical trials: | |
| Participation of family member | 544 (44.7) |
| Consultation of your physician | 774 (63.7) |
| Take more time to think before approving | 688 (56.6) |
| Researchers are willing to participate in the same study | 689 (56.7) |
| Possibility of withdrawing from the study at any time | 686 (56.4) |
| Understand the trial protocol | 1196 (98.4) |
| Sign the informed consent | 938 (77.1) |
| Results returned back the end of the study | 1128 (92.8) |
| Receiving the best medical care | 936 (77.0) |
| Helping the society | 1115 (91.7) |
| Helping in developing new medications | 1100 (90.5) |
| Getting financial compensation | 418 (34.4) |
Data are presented as actual numbers (%).
The results of the binary regression identified gender, education and previous participation as predictors for positive attitude (Table 5). Females and respondents with a higher degree had positive attitudes compared with males (OR = 1.817, 95% CI = 1.406 – 2.349, p<0.001) and to those with a school education (OR = 1.294, 95% CI = 1.017 – 1.646, p=0.036) respectively. Similarly, previous participation in a CT was independently associated with a positive attitude (OR = 1.919, 95% CI = 1.388 – 2.653, p<0.001). A very weak positive correlation was found between knowledge and attitude among Jordanians ( Spearman’s r = 0.074, p =0.01).
Table 5.
Univariate and multivariate analysis of factors affecting the participants’ attitude
| Variablea | Univariate analysis | Multivariate analysis | |||
|---|---|---|---|---|---|
| Negative attitude (607) | Positive attitude (609) | p value | OR (95% CI) | p value | |
| Age (years)b | 34 (19–81) | 34 (18–80) | 0.546 | ||
| Gender | <0.001 | <0.001 | |||
| Male | 405 (66.7) | 347 (57.0) | Ref | ||
| Female | 202 (33.3) | 262 (43.0) | 1.817 (1.406 – 2.349) | ||
| Education | 0.104 | 0.036 | |||
| School education | 258 (42.5) | 231 (57.5) | Ref | ||
| Bachelor degree | 349 (57.5) | 378 (62.1) | 1.294 (1.017 – 1.646) | ||
| Marital status | 0.841 | ||||
| Single | 218 (35.9) | 226 (37.1) | |||
| Married | 373 (61.4) | 365 (59.9) | |||
| Other | 16 (2.6) | 18 (3.0) | |||
| Occupation | 0.320 | ||||
| Unemployed | 250 (41.2) | 268 (44.0) | |||
| Employed | 357 (58.8) | 341 (56.0) | |||
| Chronic Disease | 0.918 | ||||
| No | 504 (83.0) | 507 (83.3) | |||
| Yes | 103 (17.0) | 102 (16.7) | |||
| Previous participation | 0.143 | <0.001 | |||
| No | 493 (81.2) | 474 (77.8) | Ref | ||
| Yes | 114 (18.8) | 135 (22.2) | 1.919 (1.388 – 2.653) | ||
| Knowledge | 0.251 | ||||
| Poor | 202 (33.3) | 184 (30.2) | |||
| Good | 405 (66.7) | 425 (69.8) | |||
All data expressed as n (%) of participants unless otherwise indicated
Data described as median (Interquartile range)
Bold values indicate statistical significance p < 0.05
3.4. Perception of Jordanians about clinical trials
In the current study, most of the respondents (85.3%) perceive that CTs are conducted in an ethical manner in Jordan and they don’t feel their rights being violated if their physician asks them to take part in a CT (96.3%). Despite this confidence in the health care system, only 52.9% of the respondents admitted to feel comfortable toward participating in a CT. Respondents with previous participation were significantly more comfortable toward participation compared with those that never took part in a CT (p<0.001).
Less than half (44.4%) of the respondents perceive that participation in a CT is stressful and 20.5% feel that participants are exposed to unnecessary risks during the trial. The majority (69.2%) feel that participants benefit from their participation and 56.7% feel that they receive the best medical care during the clinical trial. Most of the respondents (85.2%) believe that CTs benefit persons that might develop a disease in the future. A moderate positive correlation was found between knowledge and perception among Jordanians (Spearman’ r = 0.275, p < 0.001).
3. Discussion
Clinical trials are critical to the advancing of patient care. Bioavailability and bioequivalence studies represent most of the CTs performed in Jordan with the drug regulatory authorities taking steady steps to enhance clinical research system and phase I–IV studies are increasing in Jordan. 3, 4. Understanding the factors affecting knowledge and willingness of participants to take part in CTs is crucial for the conduction of clinical research. This study revealed important insights about the knowledge, attitudes and perception of Jordanians in regards to clinical trials.
The results in the current study demonstrated a general good knowledge of CTs among Jordanians. This finding was expected as Jordan was the first Arab country to put in practice clinical research regulations in 2001, and it is considered an important potential market for CTs in the MENA region 4, 14. Respondents recognized the importance of CTs in the development and determination of the efficacy of new drugs, in addition to the benefits of CTs at the individual and scientific levels. However, only few were aware about the existence of a legal protection of volunteers. Recent studies conducted worldwide including MENA region, showed different levels of knowledge ranging from low to- high in regard to clinical research 8, 10, 13, 15–18. Even if most of the respondents have never participated in a CT, the majority, probably driven by common sense, answered correctly questions regarding the essential elements of the informed consent. Male gender, higher education, being younger and healthy were independently associated with better knowledge. The positive influence of the aforementioned demographics on knowledge has been similarly observed, however some previous studies could not find such association 8, 18–22.
Despite the several factors encouraging Jordanians to take part in a CT, only half of the respondents in the current study had positive attitudes toward participation. A better knowledge of CTs seems not to affect attitudes toward participation. Other studies however demonstrated positive correlations between knowledge and attitude regarding CTs 8, 16, 18, 20, 22.
Consistent with other studies, female gender, higher education and previous CT participation were identified as independent factors predicting positive attitude, however, controversial data is also available 18, 22–24.
Helping the society, the development of new medications as well as ethical standards, such as the informed consent and receiving the best medical care, were encouraging factors for most of the respondents. Similarly, published results showed that patients are often willing to participate in a CT if they can help others and can receive a better treatment 6, 13, 21, 25. On the other hand, financial compensation seems not to affect the participation of Jordanians in CTs. A clear relationship between financial incentives and recruitment has not generally been established because of conflicting results 6, 25. Detailed analysis demonstrated respondents that previously took part in a CT were more affected by financial compensation compared with those that never participated (data not shown). Similarly, financial compensation was reported an encouraging factor for those that previously participated in a CT, while it does not affect the attitudes of participation-naïve individuals 26, 27.
In the present study, the results demonstrated confidence of respondents in the Jordanian health care system and being comfortable from their physician’s positive belief in a CT. A moderate positive correlation was found in the current study between knowledge and perception in regards to CTs. Jordan has a well-developed and reputable healthcare system, attributed mainly to the relative high physician to population ratio and the well-equipped hospitals 3, 4, 28. Having a patient-healthcare system relationship built on trust and ethics, is indeed important to improve the medical care and provide a good platform for clinical research in the future 21, 23, 29.
In spite of the confidence in the health care system, only half of the respondents feel comfortable in participating in a CT. Similar to other reports, concerns were raised among Jordanians regarding the risks and the stressful conditions that participants might face during participation 15, 25, 30.
The study Results show that having previously took part in a CT positively affects knowledge, attitudes and perceptions toward participation. Higher scores of knowledge, attitudes and, feeling more comfortable were observed in respondents with previous participation. All of the previous participants were male indicating that women are excluded or at least underrepresented in CTs in Jordan; this highlight an ethical concern most probably related to culture issue 31. Published data generally indicate that women have not always been adequately enrolled in CTs 32, 33.
Recruitment of participants has always been considered a challenge for the successful conduct of clinical trials worldwide, leading to globalization of CTs 2, 7, 34. In Jordan, the rate of subjects’ participation in CTs is unknown. However, interestingly 99.6% of the respondents that never took part in a CT have also never been offered to participate in the first place. Not being invited to participate is in fact an important participation-limiting factor 27.
In the current study, most of the respondents were young and healthy, which might skew the population responses. Similarly, the recruitment of Jordanians was geographically limited to the capital Amman, which might also skew the responses and the demographic characteristics.
4. Conclusion
In conclusion, there is a good general knowledge of CTs among Jordanians. However, attitude and perception are not satisfactory. Males are more knowledgeable than females while female are more encouraged to participate. Higher level of education is associated with both good knowledge and positive attitude. Taking part in a CT significantly affects knowledge, attitudes and perceptions toward participation. Educational interventions can improve awareness about ethical standards under which CTs are conducted affecting perception to participate. Promotion of clinical trials among patients and healthy individuals is also required to increase participation.
What is already known about this subject?
Clinical trials are the gold standard research methodology for the evaluation of healthcare interventions.
Bioavailability and bioequivalence studies constitute most of the clinical trials performed in Jordan with the drug regulatory authorities taking steady steps to enhance clinical research.
What does this article add?
Jordanians have good knowledge of CTs while their attitude and perception are not satisfactory.
Males are more knowledgeable than female while females, even if underrepresented in CTs in Jordan, have more positive attitudes toward participation. Higher education positively affects both knowledge and attitudes.
Having participated previously in a CT significantly and positively affects knowledge, attitudes and perceptions toward participation.
A moderate positive correlation exists between knowledge of CTs and perceptions toward participation among Jordanians.
Acknowledgement
The authors would like to thanks Prof. Dena Plemmons who provided expertise that greatly assisted the research.
The authors wish to appreciate the support of the Arab Co For Drug Industries & Medical Appliances (ACDIMA) biocenter, the International Pharmaceutical Research Center (IPRC) and the Jordan Center for Pharmaceutical Research (JCPR) for their assistance during the recruitment phase.
This project was supported by Grant 5R25TW010026–02 from the Fogarty International Center of the U.S. National Institutes of Health on behalf of the Research Ethics Program in Jordan.
Footnotes
Declaration of conflicting interests
The authors present no conflicts of interest.
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