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Year : 2022  |  Volume : 49  |  Issue : 1  |  Page : 47-54

Drug utilization pattern at the cardiac surgical outpatient clinic in a tertiary care hospital at Goa

1 Department of Cardio Vascular and Thoracic Surgery, Goa Medical College, Bambolim, Goa, India
2 Department of Community Medicine, Goa Medical College, Bambolim, Goa, India
3 Department of Pharmacology, Goa Medical College, Bambolim, Goa, India

Date of Submission04-Jul-2021
Date of Acceptance17-Oct-2021
Date of Web Publication22-Apr-2022

Correspondence Address:
Dhanya Jose
Department of Community Medicine, Goa Medical College, Bambolim - 403 202, Goa
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/jss.jss_92_21

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Background: Drug utilization research encourages rational drug prescribing practices and thus contributes to the contemporary use of drugs in the society. This study assesses the drug utilization pattern (DUP) at the cardiac surgical outpatient department of Goa Medical College hospital. We used the World Health Organization (WHO)-prescribing indicators to analyze the National List of Essential Medicines (NLEM) implementation as recommended in the National Drug Policy. Methods: We used a cross-sectional study design to analyze the DUP. We randomly selected 103 prescriptions dispensed to patients at the cardiac surgical outpatient during the study period. We critically examined these prescriptions for their consistency with WHO core drug use indicators. Results: The average number of drugs prescribed per person was 4.95. The most commonly prescribed top three drugs were antiplatelets (21.46%), beta-blockers (14.76%), and statins (13.78%). Most drugs were prescribed as single drugs (90.98%), whereas 9.02% were fixed-dose drug combinations (FDC). The combination of aspirin and clopidogrel was the most common prescribed FDC. The majority (72.44%) of the drugs prescribed were as per the NLEM 2015 list, whereas the generic name was low (2.8%). We measured Patient-Care Indicators and Facility-Specific Indicators also. The average consultation time and dispensing time were 7.76 and 3.23 min, respectively. The in-house pharmacy dispensed 82% of drugs. 93.75% of the key drugs were available in the facility. A copy of the essential drugs list was readily available in the facility. 96.67% of the patients knew the correct dosage of drugs. Conclusions: Anti-platelets and statins were the most commonly prescribed drugs. There was a high prescribing trend from the NLEM; however, the inclination to prescribe generic names was less. Patient-care and facility-specific indicators were also far from the optimal values except that of the average dispensing time.

Keywords: Aspirin, atorvastatin, beta-blockers, cardiology, coronary artery disease, cross-sectional studies, drug prescriptions, drug utilization, National List of Essential Medicines, prescribing pattern

How to cite this article:
Kolwalkar J, Jose D, Borkar S, Madhan V, Rataboli P V, Cacodcar JA, Dhupdale NY. Drug utilization pattern at the cardiac surgical outpatient clinic in a tertiary care hospital at Goa. J Sci Soc 2022;49:47-54

How to cite this URL:
Kolwalkar J, Jose D, Borkar S, Madhan V, Rataboli P V, Cacodcar JA, Dhupdale NY. Drug utilization pattern at the cardiac surgical outpatient clinic in a tertiary care hospital at Goa. J Sci Soc [serial online] 2022 [cited 2022 Nov 30];49:47-54. Available from: https://www.jscisociety.com/text.asp?2022/49/1/47/343712

  Introduction Top

Drug utilization research is a conceptual framework defined as “The marketing, distribution, prescription, and use of drugs in a society, with special emphasis on the resulting medical, social, and economic consequences.”[1] The rational use of medicines implies that “patients are provided medications appropriate to their clinical needs, adequate doses for an optimal period, and at an affordable cost to them.”[2] More than half of all drugs are prescribed, dispensed, or sold inappropriately. These ineffective and inefficient use of drugs commonly occur at health facilities in developing as well as developed countries.[3]

To formulate guidelines for rational drug prescription, we must explore clinicians' prescribing patterns. It will also help to promote safer and more cost-effective practices.[4] The World Health Organization (WHO) and the International Network of Rational Use of Drugs (INRUD) developed indicators to evaluate the performance of health-care facilities related to the utilization of drugs.[1] The WHO has set the “generic drug prescription rate” to count the use of generic drugs prescribed by a physician. The generic name is defined as a product identified by its original chemical or pharmacological name rather than the commercial brand name. It has its inherent pharmacological properties and similar potency, dosage, and bioavailability as a brand name.[5] The higher the generic drug prescription rate, the more generics medications prescribed, the less branded drugs used (and vice versa), implicates fewer health-care costs even with similar efficacy in clinical results. Studies on drug utilization patterns (DUP) have become a potential tool to evaluate the health-care system. It encourages rational drug prescription and helps to obtain data on the current use of medicines in the region.

Coronary artery disease (CAD) poses a significant financial burden on the patient.[6] CAD is the leading cause of death in developed and developing countries. An estimated 17.9 million people died from CVDs in 2020, representing 31% of all global deaths. Of these deaths, 85% are due to heart attack and stroke.[7] CAD accounted for around 15%–20% and 6%–9% of India's and US deaths. In 2016, an estimated 62.5 million and 12.7 million years of life were lost prematurely due to CAD in India and the US, respectively. The treatment of CAD is costly and can consume a significant part of the patient's income. The duration of treatment is also longer. In India, the direct cost of CAD could be 200 billion rupees. This cost would increase to 800 billion rupees if 100% of the CAD patients received the necessary treatment. Indirect costs would make the price even higher.[6]

Objectives of the study

The objectives of this study are as follows:

  • The assessment of the current prescribing pattern and the DUPs in the cardiac surgical outpatient clinics at Goa Medical College using the WHO prescribing indicators
  • To measure the degree of implementation of national drug policy by the practitioners as indicated in the prescribing drugs in the National List of Essential Medicines (NLEM)[8]
  • To assess patient care and facility indicators.

  Methods Top

Study design

It is a hospital record-based, cross-sectional study.

Study duration

The study duration was 2 months from September 2020 to October 2020. The study protocol was approved by the Institutional Ethics Committee of Goa Medical College, Bambolim, India, on August 7, 2020.

Study setting

We collected the prescriptions from Goa Medical College Hospital Pharmacy.

Sample size

As per the WHO guidelines, the minimum sample size to investigate drug indicators is 100.[1]

We also used the following formula for calculating the adequate sample size,

n = Z2 P(1−P) / d2

n is the sample size, Z is the statistic corresponding to the level of confidence, P is the expected prevalence (obtained from a similar study), and d is precision (corresponding to effect size).[9]

The confidence level aimed for is 95%, and precision of 5%, we decided to collect the prescriptions of one hundred (n = 100) adult patients of either sex who attended cardiac surgical OPD.

Study instruments

The prescriptions of one hundred (n = 100) adult patients of either sex who attended cardiology OPD were identified randomly and collected from the pharmacy.

Prescription details such as patient name, age, gender, hospital number, date of consultation, drug name, dosage, dosage form, frequency, duration, and quantity were noted and entered on case record forms.

Data analysis

We analyzed WHO core drug use indicators and additional parameters:

Group 1: Prescribing indicators:

  1. The average number of drugs per prescription
  2. Percentage of drugs prescribed by generic name versus brand name
  3. Rate of medicines prescribed from the NLEM-2015
  4. Percentage of encounters with an injection prescribed
  5. Percentage of encounters with antibiotics prescribed.

  6. Additional parameters

    1. Most typical type and class of drugs prescribed
    2. Percentage of drugs prescribed as fixed drug combinations (FDC).

    Group 2: Patient care indicators:

  7. Average consultation time
  8. Average dispensing time
  9. Percentage of drugs dispensed (PDD)
  10. Percentage of drugs adequately labeled
  11. Patients' knowledge of correct dosage.

Group 3: Health facility indicators

  1. Availability of copy of essential drugs list or formulary
  2. Availability of key drugs.

Statistical analysis

We entered the collected data in Google Sheets and analyzed descriptive statistics using Google Sheets and R programming language.

  Results Top

We analyzed 103 drug encounters, which consisted of 510 drug products. On average, we observed 4.95 drug products per prescription [Table 1].
Table 1: Details of drug utilization prescribing indices

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Prescribing indicators

Additional parameters

Different classes of cardiovascular drugs such as antiplatelets, antihypertensive drugs, statins, anticoagulants, and antianginals were prescribed. In this study, the most commonly prescribed drugs were antiplatelets (21.46%) followed by beta-blockers (14.76%), statins (13.78%), diuretics (9.25%), antidiabetics (8.46%), nitrates (7.48%), calcium-channel blockers (5.12%), angiotensin-converting enzyme inhibitors (5.12%), anticoagulants (4.13%), vitamins (3.74%), antibiotics (1.57%), proton-pump inhibitors (1.38%), cardiac glycosides (0.98%), angiotensin receptor blockers (0.98%), combined alpha and beta-blockers (0.39%), benzodiazepines (0.2%), antiarrhythmics (0.2%), and alpha-blockers (0.2%) [Figure 1]. Aspirin and clopidogrel are the preferred and commonly prescribed antiplatelet drugs. Atorvastatin is the preferred statin.
Figure 1: Different classes of prescribed drugs in the CVTS outpatient department

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Most drugs were prescribed as single drugs (90.98%) while 9.02% as a fixed-dose combination (FDC). The combination of aspirin + clopidogrel (95.56%) was the most common prescribed FDC, followed by telmisartan + amlodipine (4.44%) and aspirin + atorvastatin (2.22%) [Figure 2].
Figure 2: Different prescribed fixed-dose combinations

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Most drugs were prescribed by brand/trade name (97.20%) in this study, while only 2.80% were by generic name [Figure 3]. Thus, the study documents preference for branded drugs/trade names instead of generic prescribing. In this study, 72.44% of drugs were from the National Essential Drug List (NLEM 2015), whereas only 27.56% accounted for nonessential medications [Figure 4].
Figure 3: Percentage of drug prescribed by generic versus brand name

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Figure 4: Percentage of drugs prescribed from NLEM

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Out of single drugs prescribed, only 1.57% were antibiotics. The injectables (5.10%) were insulin prescribed to patients with diabetes mellitus.

Patient-care indicators and facility-specific indicators

We investigated the association between drugs under the NLEM list and drugs dispensed in our facility. Pearson's Chi-squared test with Yates' continuity correction was done with the R programming environment: X-squared statistic = 123.31, degree of freedom = 1, P < 2.2e-16. It showed a strong association between drugs under NLEM and drugs dispensed. Our facility could dispense most of the medicines prescribed under NLEM.

  Discussion Top

Cardiovascular diseases are causing a significant financial burden to the patient as the leading cause of morbidity and mortality worldwide.[6] The WHO has identified specific drug use indicators, mainly adopting generic drugs and adherence to the essential drug list (NLEM) to ensure the rational use of drugs.[1] The present study is to obtain the data on the current prescribing pattern and drug utilization trend of cardiac surgeons at a tertiary care hospital attached to the Goa Medical College with the ultimate goal to promote rational use of drugs among prescribers.

The average number of drug products prescribed by the cardiologist in this study is 4.95. This finding is similar to Chaudhary et al. (4.9), lesser as compared to Veeramani and Muraleedharan (5.0) and higher as compared to Slathia et al. (3.4).[10],[11],[12] Ideally, keeping the average number of drugs lower is preferred as polypharmacy leads to increased risk of drug-to-drug interactions, prescribing errors, and increased therapy cost. Our result is far above the WHO's recommended value of the average number of drugs prescribed per encounter, which is 1.3–2.0.[13]

In this study, the majority (72.44%) of drugs prescribed are from the National Essential Drug list; this number is less than Slathia et al. (82.8%), Veeramani and Muraleedharan (89.27%), and better than Chaudhary et al. (42.33%).[10],[12],[14] The standard derived to serve as an ideal is 100% according to the WHO.[13] Our study documents the preference and selection of essential drugs. The possible reason for this could be the prescriber's knowledge, understanding, and importance of essential drug concepts. The proper selection of essential medicines helps deal with most health problems and reduces unnecessary products manufactured, promoted, and marketed. Thus, the choice of essential drugs promotes rational use and is recommended by the National and International guidelines. The drugs prescribed from the CVTS outpatient department in our facility, which is not under NLEM, are FDCs, acenocoumarol, cefuroxime, cilostazol, gliclazide, prazosin, and torsemide.

In our study, most of the drugs prescribed by cardiologists are by brand/trade names (97.2%) rather than generic, constituting only 2.8%. The low selection of generic drugs was similar to a study conducted by Veeramani and Muraleedharan in Tamil Nadu, India (2.33%).[14] However, Slathia et al. in Mumbai, India, showed 6.2% of generic drugs, and by Chaudhary et al., in Nepal showed 0.1%.[10],[12] The generic prescription rate in our study is too low compared with the standard derived from serving as an ideal (100%).[13] It is preferable to prescribe drugs by generic name as it avoids duplication of drug products and reduces the cost, translating into cost-effective drug therapy. However, the issues of substandard manufacturing of generic drugs need to be accounted for, which generally lowers the therapeutic efficacy of drugs.

In the present study, the most commonly prescribed drugs are antiplatelets (21.46%) followed by beta-blockers (14.76%), statins (13.78%), diuretics (9.25%), antidiabetics (8.46%), nitrates (7.48%), calcium channel blockers (5.12%), angiotensin-converting enzyme inhibitors (5.12%), and anticoagulants (4.13%). Aspirin and clopidogrel are the most frequently prescribed antiplatelet drugs, metoprolol succinate and metoprolol tartrate among beta-blockers, and atorvastatin and rosuvastatin among statins. A study conducted by Slathia et al. in Mumbai, India, documented that the most commonly prescribed cardiovascular drugs in the cardiology department were aspirin and clopidogrel (23%), followed by statins (19.71%), beta-blockers (16%), nitrates (11.70%), angiotensin-converting enzyme inhibitors (8.03%), and calcium channel blockers.[12] Our study showed a similar trend of commonly prescribed drugs, antiplatelets followed by beta-blockers but documented a higher prescribing trend of diuretics instead of ACE inhibitors and calcium channel blockers. The study conducted by Veeramani and Muraleedharan indicates that the most commonly prescribed class of drugs are antiplatelets (67.73%), lipid-lowering (62.57%), beta-blockers (49.51%), ACE inhibitors (40.93%), angiotensin receptor blockers (30.40%), calcium channel blockers (30.11%), and diuretics (20.56%). It shows a similar trend with few differences.[11]

In the present study, we observed that 9.02% of prescribed drugs are fixed-dose combinations. The combination of aspirin + clopidogrel (95.56%) was the most common prescribed FDC, followed by telmisartan + amlodipine (4.44%) and aspirin + atorvastatin (2.22%). Slathia et al. showed that the combination of clopidogrel + aspirin was the most common prescribed FDC (23.19%), followed by aspirin + atorvastatin (20.29%) and furosemide + spironolactone (17.39%).[12] These combinations reflect the high prevalence of aspirin + clopidogrel in our study, which the prescriber can bypass to promote the generic drug prescription rate. In the study of Veeramani and Muraleedharan, a total of 13.21% of prescribed drugs were FDCs; the rest of the medicines were single drugs (86.78%). Aspirin + clopidogrel combination was the highly prescribed FDC (40.24%) which is similar to our study.[14]

In this study, we assessed all five prescribing indicators according to the WHO. We also evaluated patient care indicators [Table 2]. The average consultation time was 4.2 min. The average drug dispensing time was 3.23 min which is adequate to explain the dosage schedule of the drugs. According to WHO/INRUD, the optimum value for average consultation time is ≥10 min, and for average dispensing time is 3 min.[13] The time taken by the prescribers at the GMC in the current study is shorter than that recommended to administer a thorough patient assessment and prescribe drugs appropriately. A total of average consulting time and dispensing time is 3.7 min and 2.3 min in the study by Prasad et al. at Andhra Pradesh, India, both are 8 min in the study by Aravamuthan at Tamil Nadu, India, 4.1 min and 131.5 s in the study by Nyabuti et al. at Kenya, and 1.2 min and 8.7 s in a study by Atif et al. at Pakistan.[15],[16],[17],[18]
Table 2: Details of patient care indicators and facility indicators

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In our study, 82.28% of drugs are dispensed from the in-house hospital pharmacy, even though the prescription contains branded names. According to the recommendation by the WHO, the ideal percentage of drugs dispensed (PDD) should be 100% in a standard hospital with a good patient care rank.[13] The PDD was 76.3% in the Kenya study, 97.3% in the Pakistan study, 96.6% in the Andhra Pradesh study, and 99.8% in the Tamil Nadu study.[15],[16],[17],[18] Our facility could dispense a few drugs that are not under the NLEM list, like a fixed drug combination of aspirin and clopidogrel, acenocoumarol, cefuroxime, cilostazol, gliclazide, prazosin, and torsemide.

The in-house pharmacy did not dispense drugs in packages with labeled essential information on them. Instead of that, dispensers explained the dosage schedule to the patient while dispensing drugs in our facility. The PDD adequately labeled was 22.6% in the Kenya study, 99.3% in the Andhra Pradesh study, and 100% in the Pakistan study.[15],[17],[18]

Patients' knowledge of correct dosage is 96.67%. It was 89.3% in Prasad et al. at Andhra Pradesh, 72.4% in the Pakistan study, and 54.7% in the Kenya study.[15],[17],[18] The optimal WHO/INRUD value for patients' percentage knowledge on correct drug dosage is 100%.[13]

We also assessed facility indicators [Table 2]. The essential drug list is available in the pharmacy but not with the prescribers. The WHO/INRUD requires that all health facilities have copies of NLEM.[13] This aims to ensure prescribers' adherence to the medicines listed in the NLEM when prescribing to encourage the adequate provision of health care to patients. Only 20% of health facilities have the essential drug list in prescribing and dispensing areas in the Kenya study.[17] A copy of EDL was available at health centers in the studies conducted in Pakistan and Andhra Pradesh.[15],[18]

The percentage availability of key indicator drugs is 93.75% at the time of the survey visit. A study conducted in Andhra Pradesh, India, by Prasad et al. showed 88% of key essential drugs availability.[15] Studies from Pakistan (72.4%), Kenya (80%), Tamil Nadu, India (99.8%) revealed key drug availability as mentioned.[16],[17],[18] The WHO/INRUD recommends 100% availability of essential drugs at the health facilities. The shortage of key drugs is detrimental to patients concerning their health status and out-of-pocket expenses.[13]

Cardiologists' DUPs and trends in our study were knowledge-based and per the current treatment guidelines for cardiovascular diseases. Antiplatelet drugs and Statins dominated the prescribing practice with a high prescribing trend from the National Essential List of Medicines. However, there is a need to sensitize cardiac surgeons and make them aware of adopting generic drugs to ensure cost-effective and rational drug use.

Limitations of the study

The present study has certain limitations. It is a cross-sectional, quantitative drug utilization study conducted in a single hospital setup with a minimum sample size as per the WHO guidelines. We did not carry out the qualitative assessment of individual prescriptions. The study duration was for 2 months and hence could not capture the seasonal variations in prescribing trends. We did not assess the differences between individual prescribers.

  Conclusion Top

Antiplatelet drugs and statins dominated the prescribing pattern with a high prescribing trend from the NLEM. There is a scope to encourage cardiac surgeons to prescribe drugs by generic name. Up-to-date, knowledge about core-drug use indicators and NLEM is essential for prescribers and pharmacists. Patient-care and facility-specific indicators are far from the optimal values except that of the average dispensing time. The study also shows that drugs dispensed are not in packages with labeled essential information, which is another area to improve in future. In summary, the health-care facility should implement interventions aimed at strengthening good prescribing and patient-care practices.

Data availability

The primary data gathered by the authors which support the findings of this study are available from the corresponding author upon request.

Ethical approval

The Institutional Ethics Committee, Goa Medical College, Bambolim-Goa (India), provided ethical clearance for our study.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  Appendix Top

  References Top

World Health Organization. How to Investigate Drug Use in Health Facilities: Selected Drug Use Indicators. Geneva: WHO; 1993. Available from: https://digicollections.net/medicinedocs/printable-s2289e#d/s2289e. [Last cited on 2021 Apr 12].  Back to cited text no. 1
Holloway K, Dijk LV. The World Medicines Situation 2011. Rational use of Medicines. Geneva: WHO; 2011. p. 24.  Back to cited text no. 2
World Health Organization. The World Medicines Situation 2004. Geneva: World Health Organization; 2004.  Back to cited text no. 3
Ofori-Asenso R, Agyeman AA. Irrational use of medicines–A summary of key concepts. Pharmacy 2016;4:35.  Back to cited text no. 4
Lee SW, Aljunid SM. The direct cost of drug and prescribing pattern in the outpatient services of a teaching hospital in Malaysia. Asian J Pharm Clin Res 2018;11:120-4.  Back to cited text no. 5
Kumar L, Prakash A, Gupta SK. Assessment of economic Burden and quality of life in stable coronary artery disease patients. Indian J Med Spec 2019;10:26.  Back to cited text no. 6
  [Full text]  
World Health Organization. Cardiovascular Diseases (CVDs). WHO. Available from: https://www.who.int/news-room/fact-sheets/detail/cardiovascular-diseases-(cvds). [Last accessed on 2021 Apr 09].  Back to cited text no. 7
Ministry of Health and Family Welfare. National List of Essential Medicines (NLEM) 2015. New Delhi: Ministry of Health and Family Welfare; 2015;38. Available from: https://main.mohfw.gov.in. [Last cited on 2021 Apr 12].  Back to cited text no. 8
Daniel WW. (1999). Biostatistics: A Foundation for Analysis in the Health Sciences.  Back to cited text no. 9
Chaudhary GP, Chaudhary MK, Mustafa M, Adhikari M, Sah PK, Devkota S, et al. (PDF) Prescription Audit of Cardiac Drugs in Cardiac Outpatient: A Prospective Study. Available from: https://www.researchgate.net/publication/340828097_Prescription_Audit_of_Cardiac_Drugs_in_Cardiac_Outpatient_A_Prospective_Study. [Last accessed on 2021 Apr 09].  Back to cited text no. 10
Veeramani V, Muraleedharan A. Study on drug utilization pattern in cardiology outpatient department at tertiary care hospitals in South India: A prospective multicenter cross-sectional observational study. Int J Med Sci Public Health 2020;9:321-28.  Back to cited text no. 11
Slathia I, Jadhav PR, Deb P, Verma S. Drug utilisation study in cardiology outpatient department at a tertiary care hospital. Int J Basic Clin Pharmacol 2017;6:2276-81.  Back to cited text no. 12
Isah AO, Laing R, Quick J, Mabadeje AF, Santoso B, Hogerzeil H, et al. The development of reference values for the WHO health facility core prescribing indicators. West African Journal of Pharmacology and Drug Research 2001;18:6-11.  Back to cited text no. 13
Veeramani VP. Evaluation of Drug Utilisation Pattern in Cardiovascular Diseases Using WHO/ INRUD Prescribing Indicators at Cardiology OPD of Tertiary Care Hospitals in South India: A Multicenter Cross-Sectional Study. J Adv Med Med Res 2020;32:107-20.  Back to cited text no. 14
Prasad PS, Rudra JT, Vasanthi P, Sushitha U, Sadiq MJ, Narayana G. Assessment of Drug use Pattern Using World Health Organization Core Drug Use Indicators at Secondary Care Referral Hospital South India. Available from: https://www.cjhr.org/article.asp?issn=2348-3334;year=2015;volume=2;issue=3;spage=223;epage=228;aulast=Prasad. [Last accessed on 2021 Apr 30].  Back to cited text no. 15
Aravamuthan A, Arputhavanan M, Subramaniam K, Udaya Chander J SJ. Assessment of current prescribing practices using World Health Organization core drug use and complementary indicators in selected rural community pharmacies in Southern India. J Pharm Policy Pract 2017;10:1.  Back to cited text no. 16
Nyabuti AO, Okalebo FA, Guantai EM. Examination of WHO/INRUD core drug use indicators at Public Primary Healthcare Centers in Kisii County, Kenya. Adv Pharmacol Pharm Sci 2020;2020:3173847.  Back to cited text no. 17
Atif M, Sarwar MR, Azeem M, Umer D, Rauf A, Rasool A, et al. Assessment of WHO/INRUD core drug use indicators in two tertiary care hospitals of Bahawalpur, Punjab, Pakistan. J Pharm Policy Pract 2016;9:27.  Back to cited text no. 18


  [Figure 1], [Figure 2], [Figure 3], [Figure 4]

  [Table 1], [Table 2]


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