Abstract
Introduction
The evaluation of knowledge, attitude, and practice (KAP) of health care providers on the life-threatening drug-drug interactions (DDIs) and the implementation of specific interventions may enhance patients’ safety. The current study was designed to evaluate the KAP of healthcare providers (HCPs) on life-threatening DDIs using different drug information sources.
Methods
Validated questionnaire contains demographic data, knowledge and practice questions related to the life-threatening DDIs, and attitude towards the preferable sources of drug information. The survey forms were distributed to pharmacists as well as ward doctors in departments of cardiology, nephrology, neurology, and infectious diseases, in Penang General Hospital, Penang, Malaysia.
Results
The overall response rate for 220 distributed questionnaires was 65.45%. Knowledge level is associated with healthcare specialty (p < 0.001), with 100% houseman officer having low knowledge, years of experience (p < 0.05) (50% of the HCPs with11–15 years of experience had high knowledge) and postgraduate study (p < 0.05), which 78.2% of HCPs without postgraduate studies had a low knowledge level. An association was obtained between knowledge level and attitude towards the use of computerized interaction checker (25% and 66.7% of respondents with high knowledge level had agreed and strongly agreed, respectively, to use computerized interaction checker, p < 0.05). Respondents with high knowledge level had agreed (33%) and strongly agreed (33%) to practice screening of DDIs at admission, p < 0.05.
Conclusion
Prescribers may have insufficient knowledge to avoid potential life-threatening DDIs. These findings affirm the necessity of well-designed computerized alerting systems, in addition to highlighting on pharmacists’ role as the competent source of drug information.
Keywords
1. Introduction
Drug-drug interactions (DDIs) can be defined as ‘the pharmacological or clinical response to the administration of a drug combination different from that anticipated from the known effects of the two agents when given alone.
1
Many of the interactions could be avoided during hospital admission.2
The impact of the continuing education of healthcare providers (HCPs) will reduce the costs of the healthcare system.3
Factors that are considerably correlated with DDIs include polypharmacy, geriatric patients, and co-morbid conditions such as cardiovascular diseases.4
However, despite the importance of this topic, the information on rare but life-threatening DDIs and toxicity is often incomplete.5
There are many instances of rare but serious DDIs that could occur. Sulfamethoxazole-trimethoprim (SMX-TMP) may rarely prolong the QT interval of the electrocardiogram, in which the QT prolongation may be amplified by certain underlying risk factors such as using antiarrhythmic agents.
6
A rare but life-threatening intracranial hypertension resulting from the concomitant use of isotretinoin and tetracycline was also reported.- Drew B.J.
- Ackerman M.J.
- Funk M.
- et al.
Prevention of torsade de Pointes in hospital settings: a scientific statement from the American heart association and the American college of cardiology FoundationEndorsed by the American association of critical-care nurses and the international society for computerized electrocardiology.
J Am Coll Cardiol. 2010; 55: 934-939
7
Clinical impact of DDIs between clopidogrel and proton pump inhibitors was reported frequently.8
In addition, the use of sildenafil products sold as over the counter (OTC) may lead to a serious drop in the blood pressure among patients using nitrates.9
In intensive care units (ICU), linezolid with sympathomimetic-like properties may interact with dobutamine.10
Concomitant use of ketorolac and heparin, especially the low molecular weight heparin, interaction increases the risk of bleeding.11
In term of macrolide antibiotics which is the hepatic microsomal inhibitors, they frequently interact with CYP3A4 substrates such as clopidogrel and statins.12
,13
Besides, the chronic treatment with gemfibrozil and repaglinide may acutely lower the blood glucose level.14
Geriatric male patients who take tamsulosin are exposed to the interaction with azole antifungals (CYP3A4 inhibitor) such as voriconazole.Knowledge variability between the HCPs is due to different study backgrounds. For instance, the medical doctors are trained to focus on diagnosis and skills of writing prescriptions, while pharmacists are more concerned with pharmacology and drug-related problems.
15
Even in the same specialty, variety may be according to graduation place, postgraduate study, and years of experience.16
In conjunction, this study will investigate the possible factors related to the KAP of HCPs towards the life-threatening drug-drug interactions.2. Materials and method
This was a cross-sectional analysis carried out in February to April 2018 in Penang General Hospital in Penang, Malaysia. Survey forms were distributed by drop-and-collect method over two weeks' period to 86 doctors who were currently incharge of the wards (gastroenterology, infectious disease, general medicine, endocrinology and neurology, nephrology, cardiology, and cardiac rehabilitation) as well as 134 pharmacists. The specific wards were chosen as the drug pairs that were asked in the questionnaire were widely used by the HCPs in these wards. Therefore, It was more relevant to ask the HCPs who were familiar with all those drugs, than the ones who were not. A reminder was given to the non-respondents after the end of two weeks to increase the response rate.
The sample size was calculated from the Raosoft software. The sample size calculation was performed based on the normal distribution with the assumption of the population consists of more than 30 samples. The sample size calculation was calculated by using information related to the estimated targeted population size, confidence level (amount of uncertainty that can be tolerated), margin of error (amount of error that can be tolerated), and response (expected results). The minimum sample size calculated was 141. This number was derived based on an estimated total population of 220 subjects (86 doctors and 134 pharmacists), 95% confidence level, 5% accepted a margin of error and 50% response distribution (a conservative assumption that will derive a largest sample size from a population).
2.1 Survey instruments
The self-designed survey form was divided into four parts: Part 1 was the demographic characteristics of HCPs, including gender, healthcare specialty, place of graduation, postgraduate study specialty, and the number of years in service. Part 2 was the evaluation of knowledge towards life-threatening DDIs, which are selected from Stockley's Drug Interactions Pocket Companion. A true choice was given score 1, whereas a score 0 was given for a false choice, the (not sure) choice was considered score 2 and excluded from the total true knowledge. Categorization of knowledge level was performed using the premier Bloom's cut-off points, 80%–100% (high), 60%–79% (moderate), and less than 59% (low).
18
Part 3 was the evaluation of attitude towards the preferred method for detection of DDIs and Part 4 was the evaluation of practice of HCPs regarding DDIs. Both Part 3 and 4 were categorized as a 5-point Likert scale. The formulation of the questionnaire was applied according to a previous study.19
The self-designed survey form had undergone face and content validation among ten pharmacy lecturers, three medical specialists, one medical officer, and three pharmacists. The reliability of the survey tool was evaluated using Cronbach alpha (α).
The study followed the tenets of the last update of the Declaration of Helsinki. Ethical approval for distributing the questionnaire was obtained from the National Medical Research Register (NMRR) -17-3151-39007 (IIR). Approval was obtained from the head of each department involved in the research, followed by approval of the hospital director. Informed consent was obtained from all subjects to participate in this study.
2.2 Data analysis
The data were analyzed using SPSS version 23. Descriptive analysis was used to compute frequencies of responses from all demographic items and questions on knowledge, attitude, and practice. The chi-square test or Fisher exact test was used for cross tabulation on the nominal level to explore the association between knowledge level and demographic data, attitude, and practice. The significance level was set at a p-value less than 0.05. Kruskal Wallis test was used to compare the mean true knowledge between HCPs according to their specialty and years of experience, followed by the Mann-Whitney U test to determine the difference between pairs.
3. Results
Out of the 220 questionnaires distributed, 144 HCPs returned the questionnaires with complete answers (n = 144), reflecting 65.5% response rate. Cronbach alpha was calculated for each section with the values of 0.771 (knowledge), 0.551 (attitude) 0.837 (practice). Majority of the respondents were female (63.9%), pharmacist (49.3%), local graduates (72.2%), had no postgraduate degree (76.4%), and have 0–5 years' experiences as HCPs (73.6%). The demographics with the score range of knowledge is summarized in Table 1.
Table 1Association between the demographic data with the score range for knowledge of HCPs towards life-threatening DDIs.
| Variables | Knowledge level | p value | |||
|---|---|---|---|---|---|
| Low n (%) | Moderate n (%) | High n (%) | Total n (%) | ||
| Gender | 0.148 | ||||
| Male | 44 (84.6) | 4 (7.7) | 4 (7.7) | 52 (36.1) | |
| Female | 66 (71.7) | 18 (19.6) | 8 (8.7) | 92 (63.9) | |
| Health care specialty | 0.000a | ||||
| Pharmacist | 42 (59.2) | 18 (25.0) | 11 (15.5) | 71 (49.3) | |
| Medical Officer | 15 (75.0) | 4 (20.0) | 1 (5.0) | 20 (13.9) | |
| Houseman Officer | 53 (100.0) | 0 (0.0) | 0 (0.0) | 53 (36.8) | |
| Place of graduation | 0.904 | ||||
| Local | 80 (76.7) | 16 (15.4) | 8 (7.7) | 104 (72.2) | |
| Overseas | 30 (75.0) | 6 (15.0) | 4 (10.0) | 40 (27.8) | |
| Postgraduate study | 0.034a | ||||
| Diploma | 17 (77.3) | 5 (22.7) | 0 (0.0) | 22 (15.3) | |
| Master | 7 (58.3) | 1 (8.3) | 4 (33.3) | 12 (8.3) | |
| None | 86 (78.2) | 16 (14.5) | 8 (7.3) | 110 (76.4) | |
| Years of experience | 0.012a | ||||
| 0–5 years | 86 (81.1) | 14 (13.2) | 6 (5.7) | 106 (73.6) | |
| 6–10 years | 22 (68.8) | 7 (21.9) | 3 (9.4) | 32 (22.2) | |
| 11–15 years | 2 (33.3) | 1 (16.7) | 3 (50.0) | 6 (4.2) | |
| TOTAL | 110 (76.4) | 22 (15.3) | 12 (8.3) | 114 (100) | |
Knowledge on life-threatening DDIs.
ap < 0.05 using chi-squared or Fisher exact test.
b Blooms cut-off point for knowledge (Low: <59%, Moderate: 60–79%, High (80–100%).
c The percentages are reported as percentages of variables.
d The percentages are reported as percentages of total.
Based on Table 1, about 76.4% of the HCPs had a low level of knowledge regarding DDIs. There was a significant correlation amongst knowledge level and health care specialty, (p < 0.001), postgraduate study (p < 0.05), and years of experience (p < 0.05). Based on healthcare specialty, 100% of the houseman officers (fresh graduate of medical doctors, who were in their first year of medical practice) showed a low level of knowledge, followed by 75% medical officers and only 59.2% pharmacist. Furthermore, 78.2% of HCPs without postgraduate study had low knowledge levels and 50% of the HCPs with 11–15 years of experience had a high level of knowledge. Table 2 outlines further investigations using Kruskal Wallis and Mann-Whitney U test on the true total knowledge score, which revealed significant differences between pharmacists and houseman officers (p < 0.001), as well as medical officers and houseman officers (p < 0.001) on the knowledge level. However, there was no significant difference (using Kruskal-Wallis test) in knowledge level between master holders, postgraduate diploma holders and HCPs without any postgraduate study.
Table 2Within-group comparison of the true total knowledge score.
| Kruskal Wallis Test | p value | ||
|---|---|---|---|
| N | Mean Rank | ||
| Healthcare specialty | |||
| Pharmacist | 71 | 86.82 | <0.001a |
| Medical Officer | 20 | 93.98 | |
| Houseman Officer | 53 | 45.21 | |
| Total | 144 | ||
| Years of experience | |||
| 0–5 years | 106 | 68.92 | 0.006a |
| 6–10 years | 32 | 77.72 | |
| 11–15 years | 6 | 108.00 | |
| Total | 144 | ||
| Postgraduate Study | |||
| Diploma Degree | 22 | 70.50 | 0.167 |
| Master | 12 | 88.67 | |
| None | 110 | 71.14 | |
| Total | 144 | ||
| Mann Whitney U Test | p value | ||
| N | Mean Rank | ||
| Healthcare specialty | |||
| Pharmacist | 71 | 45.92 | 0.954 |
| Medical Officer | 20 | 46.30 | |
| Total | 91 | ||
| Pharmacist | 71 | 76.91 | <0.001b |
| Houseman Officer | 53 | 43.20 | |
| Total | 124 | ||
| Medical Officer | 20 | 58.18 | <0.001b |
| Houseman Officer | 53 | 29.01 | |
| Total | 73 | ||
| Years of experience | |||
| 0–5 years | 106 | 67.52 | 0.141 |
| 6–10 years | 32 | 76.06 | |
| Total | 138 | ||
| 0–5 years | 106 | 54.90 | 0.002b |
| 11–15 years | 6 | 84.83 | |
| Total | 112 | ||
| 6–10 years | 32 | 18.16 | 0.045b |
| 11–15 years | 6 | 26.67 | |
| Total | 38 | ||
ap < 0.05 with Kruskal Wallis test.
bp < 0.05 with Mann Whitney U test.
For the evaluation of knowledge, the respondents were asked about the predicted outcomes (in the form of life-threatening DDIs) for ten drug pairs. The highest correct answer was recorded for the question related to the DDIs between clopidogrel and omeprazole (61.8%). This is followed by DDIs between sildenafil and isosorbide dinitrate (55.6%), simvastatin and clarithromycin (42.4%), and heparin and ketorolac (42.4%). The highest unsure answer was for DDIs between dobutamine and linezolid (68.1%), followed by clopidogrel and erythromycin (59.0%) and tamsulosin and voriconazole (57.6%). The complete information can be found in Table 3.
Table 3Knowledge of HCPs towards life-threatening drug-drug interactions.
| No | Questions | Incorrect answer n (%) | Correct answer n (%) | Unsure answer n (%) |
|---|---|---|---|---|
| 1. | Acitretin + Tetracycline = Intracranial hypertension | 11 (7.6) | 35 (24.3) | 98 (68.1) |
| 2. | Amiodarone + Sulphamethoxazole/Trimethoprim = Drop in heart rate | 9 (6.3) | 55 (38.2) | 80 (55.6) |
| 3. | Clopidogrel + Omeprazole = Increase risk of stroke | 14 (9.7) | 89 (61.8) | 41 (28.5) |
| 4. | Sildenafil + Isosorbide dinitrate = Severe hypotension | 17 (11.8) | 80 (55.6) | 47 (32.6) |
| 5. | Dobutamine + Linezolid = Acute hypertensive | 16 (11.1) | 30 (20.8) | 98 (68.1) |
| 6. | Heparin + Ketorolac = Increase bleeding risk | 23 (16) | 61 (42.4) | 60 (41.7) |
| 7. | Clopidogrel + Erythromycin = Increase risk of stroke | 17 (11.8) | 42 (29.2) | 85 (59.0) |
| 8. | Simvastatin + Clarithromycin = Severe myopathy | 10 (6.9) | 61 (42.4) | 73 (50.7) |
| 9. | Repaglinide + Gemfibrozil = Severe hypoglycemia | 28 (19.4) | 37 (25.7) | 79 (54.9) |
| 10. | Tamsulosin + Voriconazole = Severe postural hypotension | 19 (13.2) | 42 (29.2) | 83 (57.6) |
a Percentages are reported as percentage of total.
3.1 Attitude towards life-threatening DDIs
The attitude towards searching information related to life-threatening DDIs is summarized in Table 4. Majority of the respondents with low knowledge level were strongly agreed and agreed to use computerized interaction checker (76.4%), having a numerous educational program on DDIs monitoring (75.5%) and asking pharmacists (70.0%). The educational program is the most preferable choice for respondents with a high knowledge level (91.7%).
Table 4Association between knowledge level and attitude of HCPs towards searching for DDIs information.
| Attitude | Knowledge level | p value | |||
|---|---|---|---|---|---|
| Low n (%) | Moderate n (%) | High n (%) | Total n (%) | ||
| 1.I prefer to search for drug interactions using computerized interaction checker. | 0.039a | ||||
| 2 (1.8) | 0 (0.0) | 0 (0.0) | 2 (1.4) | |
| 2 (1.8) | 0 0.0) | 1 (8.3) | 3 (2.1) | |
| 22 (20.0) | 0 (0.0) | 0 (0.0) | 22 (15.3) | |
| 43 (39.1) | 13 (59.1) | 3 (25.0) | 59 (41.0) | |
| 41 (37.3) | 9 (40.9) | 8 (66.7) | 58 (40.3) | |
| 0.595 | ||||
| 5 (4.5) | 2 (9.1) | 1 (8.3) | 8 (5.6) | |
| 15 (13.6) | 3 (13.6) | 3 (25.0) | 21 (14.6) | |
| 49 (44.5) | 6 (27.3) | 4 (33.3) | 59 (41.0) | |
| 33 (30.0) | 10 (45.5) | 4 (33.3) | 47 (32.6) | |
| 8 (7.3) | 1 (4.5) | 0 (0.0) | 9 (6.3) | |
| 3. I prefer to ask the pharmacist about probable drug interaction. | 0.361 | ||||
| 2 (1.8) | 0 (0.0) | 0 (0.0) | 2 (1.4) | |
| 2 (1.8) | 2 (9.1) | 1 (8.3) | 5 (3.5) | |
| 29 (26.4) | 2 (9.1) | 2 (16.7) | 33 (22.9) | |
| 49 (44.5) | 12 (54.5) | 6 (50.0) | 67 (46.5) | |
| 28 (25.5) | 6 (27.3) | 3 (25.0) | 37 (25.7) | |
| 0.283 | ||||
| 5 (4.5) | 2 (9.1) | 2 (16.7) | 9 (6.3) | |
| 22 (20) | 6 (27.3) | 3 (25.0) | 31 (21.5) | |
| 40 (36.4) | 10 (45.5) | 6 (50.0) | 56 (38.9) | |
| 34 (30.9) | 3 (13.6) | 1 (8.3) | 38 (26.4) | |
| 9(8.2) | 1 (4.5) | 0 (0.0) | 10 (6.9) | |
| 5. I prefer a frequent educational program on monitoring of drug interactions. | 0.416 | ||||
| 1 (0.9) | 0(0.0) | 0 (0.0) | 1 (0.7) | |
| 0 (0.0) | 0(0.0) | 0 (0.0) | 0 (0.0) | |
| 26 (23.6) | 2 (9.1) | 1 (8.3) | 29 (20.1) | |
| 43 (39.1) | 11 (50) | 8 (66.7) | 62 (43.1) | |
| 40 (36.4) | 9 (40.9) | 3 (25) | 52 (36.1) | |
ap < 0.05 using Fisher exact test.
b Blooms cut-off point for knowledge (Low: <59%, Moderate: 60–79%, High (80–100%).
c The percentages are reported as percentages of knowledge.
d The percentages are reported as percentages of total.
3.2 Practice on life-threatening DDIs
Table 5 is the summarization of the practice of HCPs with the association with knowledge level related to DDIs. In term of practice related to the detection and prevention of DDIs, majority of the respondents had a regular screening on DDIs during patients' admission (88%), assessment on DDIs before prescribing or dispensing medications (85%) reporting DDIs (80%) and patient counseling on suspected DDIs (79%). Moreover, all of the respondents with a high level of knowledge has a good practice related to DDIs in their department, except for 8.3% who had no regular screening on DDIs on patients’ admission.
Table 5Association between practice and knowledge of HCPs towards life-threatening DDIs.
| Practice | Knowledge level | p value | |||
|---|---|---|---|---|---|
| Low n (%) | Moderate n (%) | High n (%) | Total n (%) | ||
| 1. Screening patient's drug interactions at admission are performed regularly in my department | 0.032a | ||||
| 1 (0.9) | 2(9.1) | 1(8.3) | 4 (2.8) | |
| 5(4.5) | 3(13.6) | 0 (0.0) | 8 (5.6) | |
| 37(33.6) | 4(18.2) | 3(25.0) | 44 (30.6) | |
| 51(46.4) | 12(54.5) | 4(33.3) | 67 (46.5) | |
| 16(14.5) | 1(4.5) | 4(33.3) | 21 (14.6) | |
| 2. Assessment of drug interactions before prescribing or dispensing medications is a regular procedure in my department. | 0.197 | ||||
| 1(0.9) | 1 (4.5) | 0 (0.0) | 2 (1.4) | |
| 5(4.5) | 3(13.6) | 0 (0.0) | 8 (5.6) | |
| 39(35.5) | 7(31.8) | 3(25) | 49 (34.0) | |
| 53(48.2) | 10(45.5) | 5(41.7) | 68 (47.2) | |
| 12(10.9) | 1(4.5) | 4(33.3) | 17 (11.8) | |
| 3. Documentation of reported drug interactions is a regular procedure in my department. | 0.237 | ||||
| 1(4.5) | 0 (0.0) | 2 (1.4) | ||
| 3(13.6) | 0 (0.0) | 10 (6.9) | ||
| 6(27.3) | 7(58.3) | 52 (36.1) | ||
| 11(50.0) | 5(41.7) | 61 (42.4) | ||
| 1(4.5) | 0 (0.0) | 19 (13.2) | ||
| 4. Patient counseling about the suspected drug interactions is a regular process in my department. | 0.729 | ||||
| 1(4.5) | 0 (0.0) | 2 (1.4) | ||
| 0.729 | 2(9.1) | 0 (0.0) | 7 (4.9) | |
| 9(40.9) | 4(33.3) | 56 (38.9) | ||
| 9(40.9) | 7(58.3) | 64 (44.4) | ||
| 1(4.5) | 1(8.3) | 15 (10.4) | ||
ap < 0.05 using Fisher exact test.
b Blooms cut-off point for knowledge (Low: <59%, Moderate: 60–79%, High (80–100%).
c The percentages are reported as percentages of knowledge.
d The percentages are reported as percentages of total.
4. Discussion
In this investigation, the emphasis is on the life-threatening DDIs, as limited studies are focusing on the KAP of HCPs towards the topic, despite its importance. This study also emphasizes only a few DDIs, involving relevant drugs in the clinical practice in Malaysia.
In this study, there were associations between the level of knowledge with healthcare specialty, postgraduate study, and years of experience. Pharmacists were observed to have a higher knowledge than medical officers and houseman officers. These results may be related to the fact that medical doctors are trained to focus on diagnosis and skills of writing prescriptions, while pharmacists are more concerned with pharmacology and drug-related problems.
15
The difference of level of knowledge between medical and houseman officers are most probably related to the variability in the number of experience years. Based on the current study, the HCPs with 11–15 years of working experiences had the highest level of knowledge, followed by 6–10 years and 0–5 years. A study reported a lower DDI knowledge associated with a lack of clinical experience and this result supported the current study finding.16
Based on each question, the highest percentage of incorrect answers was for clopidogrel and omeprazole DDI. Omeprazole is frequently prescribed in the wards the stress ulcer prophylaxis. Therefore, the HCPs may be more aware and familiar with its DDI. On the other hand, the lowest percent incorrect answer of DDIs was for dobutamine and linezolid. This may be due to limited used of dobutamine mainly in intensive care unit, not in the wards. The highest percent of the unsure answer was for the DDI of acitretin and tetracycline. Tetracycline is used frequently in acne treatment and may be combined with acitretin for the same indication. It is also used in H. Pylori infection in the quadruple therapy (bismuth, metronidazole, and tetracycline) plus proton pump inhibitor.
20
,21
It is essential to check the past medical history about acitretin before prescribing tetracycline. The highest percent of the incorrect answer was for the DDI between repaglinide and gemfibrozil. Gemfibrozil decreased blood levels of triglycerides and used in diabetic metabolic syndrome so that it may be combined with insulin secretagogue such as repaglinide.22
Because there is a probability of these drugs to be prescribed together, HCPs need to be aware of the severe hypoglycemia event that may occur with these drugs combination.With regards to the attitude, HCPs preferred to search for DDI using computerized interaction checker. A few research supports this finding. In a study performed by Glassman PA et al., almost 90% of clinicians believed that drug alerts would be useful to distinguish interactions.
23
Another study performed by Yu Ko et al. in the USA in 2007 revealed that DDI alerts were not viewed as wastefulness of time and the mainstream (61%) of prescribers felt that DDI alerts had augmented their possible to prescribe safe medications. Pharmacists and physicians are documented to primarily depend on electronic references for general drug information (62% and 55%, respectively) and DDI information (51% vs. 79%).24
Also, the beneficial and vital effect of the incorporation of the DDI database such as Swedish-Finnish Interaction X-referencing) (SFINX) into primary health care records was associated with a 17% decrease in interactions per prescribed drug-drug pair in the predominance of potentially serious DDI (p = 0.042).25
SFINX is a DDI database designed for clinical decision support systems that includes over 8000 interaction pairs and had been integrated into Swedish and Finnish computerized decision support systems.26
Generally, electronic medical record system, which provides alerts on interactions between drugs prescribed for the patients automatically, has proved an effective impact in another study.27
Apart from that, most HCPs preferred frequent educational program in DDI monitoring. This will be useful especially for houseman officers and fresh graduates. The pharmacistis viewed as a reliable source of DDI information, and the majority of the HCPs preferred to ask pharmacist regarding the potential DDIs. This is congruent with studies showing effective intervention from clinical pharmacists in the prevention of DDIs and even drug-food interactions.28
, 29
Pharmacists also have a role in providing a frequent education program related to DDI to all HCPs.In term of practice, majority HCPs had a good practice related to performing DDI screening during patient admission to the hospital, assessing potential DDI before prescribing or dispensing, documenting DDIs and performing patient counseling related to DDIs. However, there were also many HCPs who are neutrally related to these practices, especially among the HCPs with a low level of knowledge. Steps necessity to be taken to make sure these practices are fully implemented by HCPs to reduce DDIs. A study has suggested that adherence to correct policies or prescription writing, an appropriate surveillance system to monitor DDIs, and promoting physician's knowledge on potentially harmful DDIs should be practiced in preventing DDIs.
30
4.1 Strength of the study
The reliability of knowledge and practice questions was acceptable (Cronbach alpha 0.771 and 0.837, respectively) so it can be expanded in a larger sample size as a novel questionnaire. Besides, the strength of this study lies in the structure of the questionnaire itself. Specific items on the sources of DDIs information is used in the questionnaire, which is different from a previous study
19
which used ‘others’ term and different methods31
as an answer to a question about information source of DDI. ‘Others’ term is not specific and did not determine the actual source of drug information. Besides, the included drug pairs in the knowledge test were formulated as an equation which makes it straight-forward as well as easy to read and understand.4.2 Limitations of the study
The Cronbach alpha for attitude questions was less than acceptable (0.551). Better construction of questions can be done in the future to increase the reliability of the questions, before it can be used on a larger scale, as a survey tool. This survey was applied only between pharmacists and doctors in some departments in a tertiary hospital (Penang General Hospital) in Malaysia, so the results may not be generalized to other hospitals in the country. A future study with more sample size, multicenter and more healthcare specialties may be needed.
5. Conclusion
In conclusion, HCPs may have insufficient knowledge to prevent life-threatening DDIs. Pharmacists had higher knowledge level than medical and houseman officers. Majority of HCPs with long years of experience had a high knowledge. Majority of HCPs had a low knowledge on the life-threatening DDIs prefers to search drug interactions using computerized interaction checkers and practice a regular screening on drug interactions during patient admission to the hospital. Pharmacists may play a role in preventing DDIS by providing information and continuous education to HCPs, as well as assessing and documenting life-threatening DDIs.
Funding
No funding
Authors’ contributions
- •MSA contributed in the conception of the work, data collection, data analysis, manuscript drafting, manuscript revising, and approval of manuscript final, all aspects of the work and agreed for all aspects of the work.
- •MAH contributed in the conception of the work, manuscript drafting, manuscript revising, manuscript final approval and agreed for all aspects of the work
- •SNH contributed in the conception of the work, manuscript drafting, manuscript revising, and manuscript final approval and agreed for all aspects of the work.
- •TME contributed in the conception of the work, manuscript drafting, manuscript revising, and manuscript final approval and agreed for all aspects of the work.
- •SMSG contributed in the conception of the work, data analysis, manuscript drafting, manuscript revising, and approval of manuscript final and agreed for all aspects of the work.
The manuscript has been read and approved by all the authors, that the requirements for authorship as stated earlier in this document have been met, and that each author believes that the manuscript represents honest work.
Declaration of competing interest
All the authors do not have any possible conflicts of interest.
Acknowledgment
We want to thank all healthcare practitioners who actively participated in this study. In addition, we would like to thank the Director General of Health Malaysia for his permission to publish this article.
References
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Article info
Publication history
Published online: May 07, 2020
Accepted:
April 26,
2020
Received in revised form:
April 20,
2020
Received:
January 10,
2020
Identification
Copyright
© 2020 INDIACLEN. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.
