drug utilisation studies

1. Drug Utilization Studies
Dr. Mansij Biswas, SYR
Department of Pharmacology & Therapeutics
Seth G S Medical College & KEM Hospital

2. Introduction & Definition:
 Pharmaco-epidemiology is the study of use and effects
or side-effects of drugs in large number of people with
the purpose of supporting the rational and cost effective
use of drugs in population, thereby improving health
outcomes.
 WHO defines drug utilization research as, “the
marketing, distribution, prescription and the use of
drugs in a society with special emphasis on the resulting
medical, social and economic consequences.”(WHO,
1977)
June 7th, 2014
INTRODUCTION TO DRUG UTILIZATION RESEARCH, WHO International Working Group For
Drug Statistics Methodology, WHO Collaborating Centre For Drug Statistics Methodology, WHO, 2003.
2

3. Looking back…
 Initiated in Northern Europe and The UK in the mid
1960s
 Arthur Engel in Sweden and Pieter Siderius in Holland
described importance of comparing drug use between
different countries and regions
 Differences in sales of antibiotics in six European
countries between 1966 and 1967 inspired WHO to
organize first meeting on drug consumption in Oslo,
1969
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4.  Constitution of WHO European Drug Utilization
Research Group (DURG)
 Development of a new unit of measurement, initially
called the agreed daily dose and later the Defined Daily
Dose (DDD), by researchers from Ireland, Norway &
Sweden
 The first study used anti-diabetic drugs as an example
 Among the first countries to adopt the DDD
methodology was the former Czechoslovakia
 First comprehensive national list of DDD was published
in Norway in 1975
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5. Why drug utilization research?
 The principal aim is to facilitate the rational use of
drugs in populations.
 Rational use of medicines (RUM) is defined as
“Patients receive medications appropriate to their
clinical needs, in doses that meet their own individual
requirements, for an adequate period of time, and at the
lowest cost to them and their community” (WHO, 1985)
June 7th, 2014
Promoting Rational Use of Medicines: Core Components - WHO Policy Perspectives on
Medicines, No. 005, September 2002 5

6. Objectives:
 Description of drug use pattern
 Early signals of irrational use of drugs
 Interventions to improve drug use – follow up &
assessing the impact
 Quality control of drug use
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7.  Description of drug use pattern : -
Drug utilization research will increase our understanding of
how drugs are being used by-
 Estimating the numbers of patients exposed to specified
drugs within a given time period.
 Getting extent of use at certain moment or area.
 Estimating to what extent drugs are properly used,
overused or underused.
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8.  Determining pattern or profile of drug use and the
extent to which alternative drugs are being used to
treat particular conditions.
 Comparing the observed patterns of drug use for the
treatment of certain disease with current guidelines.
 Giving feedback of the drug utilization data to
prescribers.
 Assessing the potential magnitude of the problem
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9.  Early signals of irrational use of drugs:
 Comparing drug utilization patterns and cost
between different regions or time period
 Comparing observed patterns of drug use with
current recommendation or guidelines for the
treatment of certain disease
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10.  Interventions to improve drug use-follow
up:
 Monitoring and evaluating the effects of measures
taken to improve undesirable patterns of drug use
 Following the impact of regulatory changes or
changes in the insurance or reimbursement schemes
 To which extent promotional activities of the
pharmaceutical industry and educational activities of
the society impact on the patterns of drug use
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11.  Quality control of drug use:
Drug use should be controlled according to a quality control
cycle that offers a systematic framework for continuous
quality improvement
Step 1 : PLAN –
Analyze the current
situation to establish
plan for improvement
Step 2 : DO –
Implement the plan on
small scale
Step 4 : ACT – Revise
plan or implement plan
Step 3 : CHECK –
Check to see if
expected results are
obtained
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on large scale

12. Types of drug use information
 Drug based information
 Problem or encounter based information
 Patient based information
 Prescriber based information
 Cost based information
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13. A) Drug based informations
◦ Data on drug use on various levels, and
information on indications, doses and dosage
regimen is usually necessary
◦ Level of drug use aggregation : The level at
which data on drug use are aggregated will
depend on question being asked.
 E.g. Hypertension
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14.  Indication –
◦ For drugs with multiple indications, it will
usually be important to divide data on use
according to indication to allow a correct
interpretation of the overall trends.
E.g.-
◦ antibiotic utilization
◦ Use of beta-blockers
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15. B) Problem based informations
◦ Useful to address the question – how a particular
problem is managed.
 Questions that might be addressed:
◦ Does the severity of the disease influence the
choice of single or combination therapy ?
◦ Is the management of newly-presenting patients
different to that of patients already receiving
treatment ?
◦ Are there likely to be any drug interactions with
co-prescribed treatments ?
◦ Is the choice of drug influenced by evidence
based outcome data ?
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16. C) Patient based informations
Information on demographic factors and other
details about the patient are useful
Age distribution – to assess the likelihood of severe
adverse effects with some drugs
Comorbidities of patient
Knowledge, beliefs and perceptions of patients and
their attitudes to drugs are important
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17. D) Prescriber based informations
This information is useful to understand how
and why drugs are prescribed.
◦ Some questions that might be addressed:
 Are prescribing profiles influenced by the
prescriber’s medical education?
 Do the prescribing profiles of specialists differ from
those of general practitioners ?
 Does the age or gender of the prescriber influence
the prescribing profile?
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18.  Are there differences in prescribing behavior
between urban and rural practices or between
small and large practices ?
 Who are those prescribers who rapidly adopt to
recently released drugs ?
 Can the factors that determine and change
prescribing behavior be identified ?
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19. E) Cost based informations
It will always be important in managing policy
related to drug supply, pricing and use.
E.g. Use of antipsychotic drugs in Australia
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20. The DUS cycle:
Planning
Data
collection
Evaluation
Feedback of
results
Feedback of
results
Interventions
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Reevaluation

21. Steps involved in
conducting a drug
utilization study:-
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22. Step 1:- Identify drugs or therapeutic
areas of practice for inclusion in the
program
Drug-use Chain
a) The systems and structures surrounding drug use
 e.g. how drugs are ordered, delivered and administered in
a hospital or health care facility
b) The processes of drug use
 e.g. what drugs are used and how they are used and does
their use comply with the relevant criteria, guidelines or
restrictions
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23. c) The outcome of drug use
 e.g. efficacy, adverse drug reactions and the use of
resources such as drugs, laboratory tests, hospital
beds or procedures.
 Drug utilization studies can be targeted towards any
of the above links in the drug use chain.
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24.  Generally drugs with a high volume of use, high cost or
high frequency of adverse drug reactions are subjected to
DU studies
 Common targets:-
 Commonly prescribed drugs e.g. Antibiotics, PPIs, etc.
 Drugs with significant drug interactions e.g. Warfarin,
Phenytoin
 Expensive drugs e.g. LMWH, Cephalosporins
 Newer drugs
 Drugs with a narrow therapeutic index e.g. Digoxin,
Theophylline, Lithium
 Drugs with serious ADRs e.g. aminoglycoside, NSAIDs etc.
 Drugs in high risk patients e.g. elderly, pediatric patients
 Drugs in the management of common conditions e.g. RTI or
UTI, HTN, T2DM etc
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25. Step 2:- Design of study
In designing the DU study, observational research methods
are more commonly used.
 Accordingly, DU study can be
Either :-
• Quantitative
• Qualitative
Or :-
 Cross-sectional
 Longitudinal
 Continuous longitudinal
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26.  Quantitative:-
Used to describe present situation and the trends in the
drug prescription and drug use at various levels of the
health care system.
 Qualitative:-
Assess the appropriateness of drug utilization and link
the prescribing data to reasons for prescribing. It can be
referred as Drug Utilization Review or Drug Utilization
Evaluation. This process is one of the
therapeutic/prescription audit.
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27. Cross sectional studies-
 Provide a snapshot of drug use at a particular time like
over a year, a month or a day
 Used for making comparisons with similar data
collected over the same period in a different country,
health facility or a ward
 Can be carried out before and after an intervention
 Studies can simply measure drug use, or can be utilized
to assess drug use in relation to guidelines
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28. Longitudinal studies-
 Data can be on total drug use or on a statistically valid
samples from pharmacies or medical practices.
 Often obtained from repeated cross sectional surveys.
 Data collection is continuous but the practitioner surveyed
and therefore patients are continuously changing.
 Such data gives information about overall trends but not
about prescribing trends.
 Provide information about concordance with treatment
based on the period between prescriptions, duration of
treatment, PDD etc
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29. Continuous longitudinal study-
◦ This data can address a range of issues
including reasons for change in therapy,
adverse effects and health outcomes
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30. Step 3:- Define criteria and
standards
 With an exhaustive literature search, identify the
key literature in the chosen area of interest and
the drug criteria that can be derived from this
evidence based literature.
 Must be valid, unambiguous, realistic, easily
measured and outcome oriented.
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31. Step 4:- Design the data collection form
 It is impossible to address all aspects of use for each
◦ Patient demographics
◦ Prescriber details
◦ Indication/
Contraindications
◦ Side/adverse effects
◦ Dosing information
◦ Drug or drug class duplication
◦ Drug interactions
◦ Monitoring of drug therapy
◦ Patient education/instructions
◦ Cost of therapy
individual drug BUT
 It is important to limit data collection to only the most
important and relevant aspects of drug use
 Aspects of drug use commonly surveyed are -
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32. Step 5:- Data collection
 Physicians, pharmacists and nurses make
ideal data collectors.
 Different types of drug use information
are required depending upon the problem
being examined.
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33. Source of data
◦ Large databases
◦ Data from drug regulatory agency
◦ Supplier (distribution) data
◦ Practice setting data
◦ Community setting data
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34. Large databases:-
◦ Efficient use of health care resources - Computer
databases or medical record sections
◦ May be international, national or local- comparative
studies can be planned at various levels.
◦ May be diagnosis linked or non-diagnosis linked
◦ Diagnosis linked data enable drug use to be
analyzed according to patients characteristics,
therapeutic groups, diseases or conditions and,
clinical outcome.
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35. Data from drug regulatory agencies:-
 Are repositories of data on which drugs have been
registered for use, withdrawn or banned within a
country.
 Agencies have the legal responsibility of ensuring the
availability of safe, efficacious and good quality drugs
 Possible to obtain data on the number of drugs
registered in a country from such agencies.
 Importation data like product type (i.e. generic or
branded), volume, port of origin, country of
manufacture, batch number and expiry date may be
collected.
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36. Supplier (distribution) data:-
 Drug importation; local manufacture; customs
service, whole salers
 In countries where licenses are required from drug
regulatory authorities before importation of drugs
 Generally be used to describe total quantities of
specific drug or drug group, origins of supplies
and type (i.e. branded or generic)
 Distribution at different levels of supplies can be
compared
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37. Practice setting data:-
Generate indicators that provide information on
prescribing habits and aspects of patient care.
 Prescribing data
 Dispensing data
 Aggregate (facility) data
 Over-the-counter and pharmacist-prescribed drugs
 Telephone and internet prescribing
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38.  Prescribing data:
◦ Usually extracted from outpatient and inpatient
prescriptions.
◦ Information that may be obtained from
prescriptions includes
 Patient’s demography
 Drug name, dosage form, strength, dose, frequency of
administration and duration of treatment.
 Where diagnoses are noted on prescriptions, is
possible to link drug use to indications.
 Trends in utilization for specific drugs and diseases
can also be established.
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39.  Dispensing data:-
Drug dispensing is a process that ends with a client
leaving a drug outlet with a defined quantity of medication
and instructions for using it.
◦ Information available from dispensers may include
 Drug (s) prescribed
 Dose(s) prescribed
 Average number of items per prescription
 Percentage of items prescribed that were actually supplied
(an indicator of availability)
 Percentage of drugs adequately labeled
 Quantity of medications dispensed
 Cost of each item or prescription.
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40.  Aggregate data
◦ Source include – pharmacy stock and dispensing
records, medication error records, adverse drug reaction
records and patient medical records.
◦ Used to obtain information on
 The cost of individual drugs and classes of drug
 The most and least expensive drugs
 The per capita consumption of specific products.
 The prevalence of adverse drug reactions.
 The prevalence of medication errors.
 The percentage of the budget spent on specific drugs
or classes of drug.
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41.  Over-the-counter and pharmacist-prescribed
drugs:
◦ Pharmacists and other drug outlet managers may
prescribe over the counter (OTC) preparations or
pharmacist prepared drugs that do not require
prescription by physician.
◦ When such information is available from stock or
dispensing records, it broadens the understanding of
drug utilization patterns.
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42.  Telephone and Internet prescribing:
 Mostly in developed countries.
 Innovative ways need to be devised to collect
information on this type of transaction.
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43.  Community setting data:-
 Drugs available in households have either been
prescribed or dispensed at health facilities,
purchased at pharmacy or are over the counter
medications.
 The drugs may be for the treatment of current
illness or are left over from previous illness.
 Data can be collected by performing household
surveys, counting left over pills etc.
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44. Step 6:- Evaluate results
Data evaluation is the most critical step in a DUS
 Summarize data into the major categories of results
 Check where exactly the data shows deviation from the
guidelines and usage criteria
 Check whether true deviation exists
 Evaluate reasons for this deviation
 May be necessary to redefine the criteria
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45.  Reasons for deviation may include:
◦ Drug being used for new indication
◦ Outdated procedures
◦ Inadequate resources
◦ Gaps in knowledge or misinformation /
misunderstanding
 Evaluation is done with the help of:-
Drug Utilization Metrics
Drug Use Indicators
Drug classification systems
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46. Drug utilization metrics include:-
 Defined daily dose
 Prescribed daily dose
 Other units for presentation of volume
 Cost
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47. Defined daily dose (DDD):-
The DDD is the assumed average maintenance dose per
day for a drug used for its main indication in adults.
DDD is a unit of measurement and does not necessarily
correspond to the recommended or prescribed daily dose
(PDD).
Doses for individual patients and patient groups will
often differ from the DDD as they must be based on
individual characteristics (e.g. age and weight) and
pharmacokinetic considerations.
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48.  It give a rough estimate of consumption and not an exact
picture of actual use.
 DDDs provide a fixed unit of measurement independent
of price, currency, package size and strength enabling
the researcher to assess trends in drug consumption and
to perform comparisons between population groups.
 Drug utilization figures should ideally be presented as
numbers of DDDs per 1000 inhabitants per day or,
when drug use by inpatients is considered, as DDDs per
100 bed-days.
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49.  DDDs per 1000 inhabitants per day:-
◦ Provide a rough estimate of the proportion of the
study population treated daily with a particular drug or
group of drugs.
◦ E.g.-
10 DDDs per 1000 inhabitants per day indicates that 1%
of the population on average might receive a certain
drug or group of drugs daily.
◦ Most useful for chronically used drugs
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50.  DDDs per inhabitant per year:-
◦ Estimate of the average number of days for which
each inhabitant is treated annually
E.g. -
◦ 5 DDDs per inhabitant per year indicates that the
utilization is equivalent to the treatment of every
inhabitant with a five-day course during a certain year.
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51.  DDDs are not established for:-
◦ Topical products
◦ Sera, vaccines
◦ Antineoplastic agents
◦ Allergen extracts
◦ General and Local anesthetics
◦ Contrast media
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52. Prescribed daily dose (PDD):-
 The prescribed daily dose (PDD) is defined as the
average dose prescribed according to a representative
sample of prescriptions.
 Can be determined from studies of prescriptions or
medical or pharmacy records
 Gives the average daily amount of a drug that is actually
prescribed
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53.  The PDD can vary according to both the illness treated
and the national therapeutic traditions.
 The PDDs differ:
◦ Between countries and ethnic groups
◦ Between areas or health care facilities within
the same country
◦ For different indications of the same drug
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54.  PDD does not necessarily reflect actual drug
utilization.
 Specially designed studies including patient
interviews are required to measure actual drug
intake at the patient level (i.e. the consumed
daily dose).
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55. Other units for presentation of volume:
These units can be applied only when the use of a single
drug or of well defined combination product is evaluated.
 Grams of active ingredient:-
◦ Drugs with low potency will account for a larger
fraction of the total than drugs with high potency
◦ Combined products may also contain different
amounts of active ingredients from plain products
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56.  Number of tablets:-
◦ Counting numbers of tablets does not reflect the
variations in strengths of tablets, with the result that
low-strength preparations contribute relatively more
than high-strength preparations to the total numbers
 Numbers of prescriptions:-
◦ Do not accurately reflect total use, unless total
quantities of drugs per prescription are also considered.
◦ Valuable in measuring the frequency of prescriptions
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57. Cost:-
◦ Cost figures are suitable for an overall analysis of
expenditure on drugs.
◦ International comparisons based on cost parameters
can be misleading and have limited value in the
evaluation of drug use.
◦ Difficulties in evaluation may be due to
 Price differences between alternative preparations
 Fluctuations in currency
 Changes in price
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58. Drug Use Indicators:-
 Prescribing indicators
◦ Average number of drugs per encounter
◦ Percentage of drugs prescribed by generic name
◦ Percentage of encounters with an antibiotic prescribed
◦ Percentage of encounters with an injection prescribed
◦ Percentage of drugs prescribed from essential drugs
list or formulary
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59.  Patient care indicators
◦ Average consultation time
◦ Average dispensing time
◦ Percentage of drugs actually dispensed
◦ Percentage of drugs adequately labelled
◦ Patients' knowledge of correct dosage
 Facility indicators
◦ Availability of copy of essential drugs list or formulary
◦ Availability of key drugs
◦ Availability of clinical guidelines
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60.  Complementary drug use indicators
o Average medicine cost per encounter
o Percentage prescriptions in accordance with clinical
guidelines
o Percentage of patients treated without drugs
o ** WHO-INRUD (International Network for the
Rational Use of Drugs) –WHO-1993
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61. Prescribing indicators:-
1. Average number of drugs per encounter
total number of different drug products prescribed
Average = --------------------------------------------------------------
number of encounters surveyed
2. Percentage (%) of drugs prescribed by generic name
number of drugs prescribed by generic name × 100
% = ---------------------------------------------------------------
total number of drugs prescribed
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62. 3. Percentage of encounters with an antibiotic prescribed
4. Percentage of encounters with an injection prescribed
Number of patient encounters during which an antibiotic or an
injectable are prescribed x 100
% = -----------------------------------------------
Total number of encounters surveyed
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63. 5. Percentage of drugs prescribed from essential drugs list
or formulary
The number of products prescribed which are listed on the
essential drugs list or local formulary x 100
% = --------------------------------------------------
The total number of drugs prescribed
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64. Patient care indicators:-
1. Average consultation time
Total time for a series of consultation
Average=------------------------------------------------------
Number of consultations
2. Average dispensing time
Total time for dispensing drugs to a series of patients
Average=------------------------------------------------------
Number of encounters
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65. 3. Percentage of drugs actually dispensed
number of drugs actually dispensed
at the health facility × 100
%= -------------------------------------------------------------
total number of drugs prescribed
4. Percentage of drugs adequately labeled
number of drug packages containing at least
patient name, drug name and when × 100
the drug should be taken
%= -----------------------------------------------------------------
total number of drug packages dispensed
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66. 5. Patients' knowledge of correct dosage
 To reliably evaluate the correctness of patients'
responses about when they are to take the drugs, clear
guidelines should be developed about common dosage
regimens
number of patients who can adequately report the dosage
schedule for all the drugs x 100
%= --------------------------------------------------------------
total number of patients interviewed
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67. Facility indicators:-
1. Availability of copy of essential drugs list or formulary
2. Availability of clinical guidelines
◦ A national essential drugs list or a local formulary and a
clinical guideline must exist
◦ Scored as ‘Yes’ or ‘No’, per facility
3. Availability of key drugs
number of specified products actually in stock × 100
% = ----------------------------------------------------------------
total number of drugs on the checklist
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68. Model list of Key Drugs for testing drug
availability:-
Diarrhoea oral rehydration salts
cotrimoxazole tablets
Acute respiratory tract infections cotrimoxazole tablets
procaine penicillin injection
paediatric paracetamol tablets
Malaria chloroquine tablets
Anaemia ferrous salt + folic acid tablets
Worm infestations mebendazole tablets
Conjunctivitis tetracycline eye ointment
Skin disinfection iodine, gentian violet or local alternative
Fungal skin infection benzoic acid + salicylic acid ointment
Pain/fever acetylsalicylic acid or paracetamol tablets
Prophylactic drugs retinol (vitamin A)
ferrous salt + folic acid tablets
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69. Drug classification system:-
 The main purpose of having an
international standard is to be able to
compare data between countries.
 Different classification systems : -
◦ Anatomical Therapeutic Chemical (ATC)
classification develop by Norwegian researchers.
 serve as a tool for presenting drug utilization statistics
 recommended by WHO for international comparisons
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70. ◦ Anatomical Therapeutic (AT) classification developed by
the European Pharmaceutical Market Research
Association (EPhMRA)
 The EPhMRA classification system is used worldwide
by IMS (International Marketing Services) for
providing market research statistics to the
pharmaceutical industry.
June 7th, 2014 70

71. Step 7:- Provide feedback of results
 Prepare a scientific interpretation of the results
rather than a value judgment.
 Success of any DUS depends on feedback of
results to prescribers, other hospital staffs
involved in the study and to administrative
heads.
 The results can also be circulated to hospital
staff via newsletters or the hospital’s academic
meetings.
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72. Step 8:- Develop and implement
interventions
 If a drug use problem is identified the next step is to
consider how the problem can be addressed.
 Interventions:-
◦ Educational - educational meetings, development of
protocols, letters to individual physicians.
◦ Operational - modification of drug order forms,
development of stringent drug use policy, manual or
computerized reminders, prescribing restrictions,
formulary additions/deletions etc.
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73. Step 9:- Re-evaluate to determine
if drug use has improved
 Drug use and prescribing patterns need to be
monitored to determine the success of intervention
 Re-evaluation is usually done 3-12 months after the
introduction of the intervention
 Collection of data as in original DUS
 Should be a continuous process at regular interval
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74. Step 10:- Re-assess and revise the
DUS program
Results of the previous DU studies help to
improve quality, efficacy and effectiveness
of future DU studies.
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75. Step 11:- Feedback results
 Circulate results of the DUS
 Obtain opinions about success of interventions
and improvement of drug use.
 Analyze and act accordingly
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76. DU 90%
 Reflects the number of drugs that account for 90% of
drug prescriptions and adherence to local or national
prescription guidelines
 Can be applied at different levels
◦ Individual prescriber
◦ Group of prescribers
◦ Wards
◦ Hospitals
◦ County
 Gives a rough estimate of the quality of prescribing.
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77. Drug utilization evaluation
 Drug utilization evaluation (DUE) is defined as an
authorized, structured, ongoing review of physician
prescribing, pharmacist dispensing and patient
using medication.
 DUE is ongoing, systematic process designed to
maintain the appropriate and effective use of drugs
 Synonymous- Drug Utilization Review (DUR)
 Medication use evaluation (MUE) is similar to
DUE but emphasizes on improving patient’s clinical
outcome and individual quality of life.
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78. Objectives of DUE:-
 To ensure that drug therapy meets current
standards of care
 To control drug costs
 To prevent problem related to medication, ADRs
 To evaluate effectiveness of drug therapy
 To identify areas of practice that require further
education of practitioners.
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79. Classification of DUE:
A) Prospective DUE:-
◦ Involves evaluating a patient’s planned drug therapy
before a medication is dispensed.
◦ Pharmacists perform prospective reviews by assessing
prescription medication’s dosage and it’s directions
and reviewing patient information for possible drug
interactions or duplication of therapy.
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80.  Typical criteria reviewed in prospective
studies include the following:-
 Indications
 Drug selection
 Doses prescribed
 Dosage form and routes of administration
 Duration of therapy
 Costs
 Therapeutic duplication
 Quantity dispensed
 Contraindications
 Therapeutic outcomes
 Adverse drug reactions and drug interactions
 Generic substitution
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81. B) Concurrent DUE:-
◦ Performed during the course of treatment and involves
ongoing monitoring of drug therapy to ensure positive
patient outcomes.
 Typical criteria reviewed:-
◦ Drug interactions
◦ High or low dosages
◦ Duplicate therapy
◦ Drug-disease interaction
◦ Over and under utilization
◦ Drug-age precautions
◦ Drug-gender precautions
◦ Drug-pregnancy precautions
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82. C) Retrospective DUE :-
◦ Simplest to perform since drug therapy is
reviewed after the patient has received
medication.
◦ Patients medical chart or computerized
records are screened to determine whether the
drug therapy met approved criteria.
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83.  In retrospective studies, the criteria
reviewed include:-
 Evaluation of indications and contra-indications
 Monitoring high cost medicines
 Comparison of prescribing between physicians
 Cost to patient
 Over and under utilization
 Incorrect drug dosage
 Inappropriate duration
 Adverse drug reaction
 Drug interactions
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84. Statistical application in Drug
utilization research:-
 Statistical Package for social science (SPSS) can be
used.
 Chi square test can be used to test the difference
between the proportions.
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85. Future Perspectives:
 The study of drug utilization in an evolving field.
 The use of large computerized databases that allow
linkage of drug utilization data to diagnosis, subject to
some inherent limitations, is contributing to expand this
area of study.
 Importance of drug utilization studies in
pharmacoepidemiology has been increasing due to their
close association to other areas like- public health,
pharmacovigilance, pharmacoeconomics and
pharmacogenetics
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86. Conclusion:-
 Successful research in drug utilization requires
multidisciplinary collaboration between clinicians,
clinical pharmacologists, pharmacists and
epidemiologists.
 Without the support of the prescribers, this research
effort will fail to reach its goal of facilitating the
rational use of drugs.
 Only by a combination of regulatory, informative and
educational actions, together with a general
improvement of the quality of in and out-patient
medical care in the National Health System, the use of
drugs can be more rational.
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