Добавил:
Sekretar
kiopkiopkiop18@yandex.ru
t.me/Prokururor I Вовсе не секретарь, но почту проверяю
Опубликованный материал нарушает ваши авторские права? Сообщите нам.
Вуз:
Предмет:
Файл:Ординатура / Хирургия / Библиотека им академика М.И. Перельмана / Книга_5593_Библиотеки_им_академика_М_И_Перельмана.pdf
Access to medicines and prescribing – introduction CHAPTER 16
Box 16.3
Minor ailments treated by pharmacists as part
of minor ailment schemes in the UK
Athlete’s foot
Bites and stings
Constipation
Contact dermatitis
Cough
Diarrhoea
Dyspepsia
Earache
Hay fever
Headache
Head lice
Mouth ulcers
Nasal symptoms
Sore throat
Teething
Temperature
Vaginal thrush
Viral upper respiratory tract infection (URTI)
pharmacists and primary care trusts and therefore
there is no universally agreed minor ailment scheme.
However, all minor ailment schemes should have a
formal written protocol that sets out how the scheme
should operate.
There are three main types of intervention that
pharmacists can make when participating in a minor
ailment scheme and schemes could involve one or
more of these interventions. The first of these
involves providing advice to the patient. The second
involves the patient receiving a medicine and this
could be via the pharmacist writing a prescription
for a pharmacy only medicine or supplying a product
via a patient group direction. When pharmacists prescribe medicines in a minor ailment scheme the medicine is usually from a locally agreed formulary. The
third intervention is referral to a GP and many of the
schemes include a fast track referral allowing patients
who have been reviewed by a pharmacist to be seen
more quickly by the GP should their condition warrant such speed. The arrangements for referral on to a
minor ailment scheme also vary between different
schemes with some schemes allowing self-referral
by patients and others requiring referral from a
healthcare professional or a practice receptionist.
The arrangements for payments for any product supplied via a minor ailment scheme vary between different
schemes. In some schemes patients have to pay the full
cost of the product but in others the costs are met by
trusts for all patients and in some only for those patients
exempt from the normal prescription levy.
Influences on prescribing
Prescribers must have an awareness of factors with
potential to influence prescribing decision making and
take steps to ensure that their decision making is not
adversely affected by these influences. Researchers
have been investigating medical prescribing decision
making for many years and there is now an extensive
amount of literature on the factors that can influence
medical prescribing. By comparison there is much less
written about non-medical prescribing, which means
that we must consult the medical literature to review
the factors likely to influence prescribing.
A number of patient factors have been reported to
have an influence on medical prescribing decision
making (Bradley 1992). The age of the patient has
been reported to cause prescribers discomfort, with
the very old and very young being responsible. In such
cases prescribers should question whether they
should prescribe for any group of patients where they
lack experience. Patients who were well known to the
prescriber were identified as a source of discomfort
and these included frequent attenders at the practice
and patients considered to be untrustworthy. Patients
deemed untrustworthy by the prescriber, perhaps
through the previous misuse of drugs, deserve the
same consideration as other patients, although prescribers should be cautious regarding requests for
items liable for misuse. The patient’s social class,
ethnic background and educational status were also
reported to cause discomfort for some prescribers. It
is obviously not acceptable to allow these factors to
influence prescribing. It has been reported that
patients affected prescribing decision making through
demand for prescription items, although other
researchers have suggested that doctors may overestimate this pressure to prescribe (Stevenson et al
1999). Prescribers should never assume patients
want a prescription. They should explore what the
patient feels about their condition as many patients
visit healthcare professionals to receive reassurance
that they do not have a serious problem rather than
to get medicines to treat symptoms.
The characteristics of a product were also reported to influence prescribing decision making
(Bradley 1992). Specific groups of products, such as
antibiotics, benzodiazepines, cardiovascular drugs,
159
SECTION THREE Pharmacy prescribing and selection of medicines
non-steroidal anti-inflammatory drugs (NSAIDs),
tranquillizers, antidepressants and sleeping tablets
were reported to cause discomfort for prescribers.
The important aspect for non-medical prescribers
may not be the actual product that caused discomfort
but rather the reasons for the discomfort. These included safety, their own expectations, appropriateness
of treatment and uncertainty over diagnosis. Ensuring
that prescribing decisions are based upon the best
available evidence should help to minimize discomfort
over the first three of these reasons. The last reason
can be more difficult as there are situations, such as
diagnosing mental health problems and diagnosing ailments in young children, where a suspected diagnosis
is difficult to confirm or may not be confirmed until
after a period of time, although the patient’ssymptoms are such that they require immediate management. Living with uncertainty can be difficult but
informing the patient or their carer regarding the uncertainty and what action you recommend should
help minimize its impact. A product’s cost has been
reported to have an impact on prescribing for some
prescribers (Denig & Haaijer-Ruskamp 1995). The
impact of cost on prescribing was related to the condition being treated such that the effects of cost on
prescribing were greater for self-limiting conditions
compared to conditions perceived to be serious.
The time available for a consultation with patients
has been noted as a factor that can affect the volume
of prescriptions written (Muller 1972). It has been
suggested that having too little time with patients
meant that it was easier to prescribe, rather than to
explain why no prescription was required. This is
obviously not an acceptable reason for prescribing.
Prescribers must consider the time management of
their consultations and determine strategies for eliciting patients’ views on drugs and the management of
their symptoms, as well as strategies to end a consultation without issuing a prescription.
Many studies have concluded that representatives
from the pharmaceutical industry were the most
commonly used source of information by prescribers
when they were prescribing new drugs for the first
time (McGettigan et al 2000; Prosser et al 2003).
Interestingly, several studies that compared the quality of prescribing with the source of information used
by the prescriber reported that poorer quality prescribing was associated with a higher use of information originating from the pharmaceutical industry
(Haayer 1982).
Several studies have noted the influence of colleagues on medical prescribing decision making. It has
been reported that hospital consultants are a major
influence on the prescribing of GPs but fellow GPs
are much less of an influence (Jones et al 2001).
Colleagues can be a valuable source of information
on developments in health care and sharing experiences with fellow professionals can aid the development of strategies to manage patient consultations
discussed earlier. Establishing professional links with
other prescribers – not just pharmacist prescribers but
GPs, hospital medical prescribers, nurses and other
non-medical prescribers – is to be encouraged.
Clinical governance in prescribing
Clinical governance is about regularly monitoring and
continually updating services in a way that increases
accountability for all activities with the overall aim of
maintaining and improving standards of care. Prescribing is no different from any other pharmaceutical
service and should comply with the principles of clinical governance. There should be clear lines of responsibility and accountability within organizations with
regards to all aspects of prescribing so that prescribers
and their managers are aware of their roles. Organizations should promote clinical audits and prescribers
should participate in these audits where appropriate,
as well as auditing their own prescribing performance
against standards such as the National Prescribing
Centre Competency Framework (see Ch. 17). Taking
any drug will put a patient at risk of side-effects or
adverse drug reactions. Prescribers must balance
these risks against the potential benefits of the treatment. Organizations and individual prescribers must
document errors and near misses so that all can learn
and standards can be continually improved. Prescribers should have up-to-date therapeutic knowledge,
be aware of national and local clinical guidelines
and base their prescribing decisions on the best evidence available. Achieving concordance is key to ensuring effective treatment and prescribers must
communicate the benefits and risks of the available
treatment options to patients or their carers.
Code of Ethics
The Royal Pharmaceutical Society of Great Britain
(RPSGB) Code of Ethics directs pharmacist prescribers to prescribe responsibly and in the patient’s best
interests. It provides further direction for pharmacist
160
Access to medicines and prescribing – introduction CHAPTER 16
Box 16.4
Code of Ethics and standards service
specification for pharmacist prescribers
Limitations Pharmacist prescribers must limit their
prescribing to areas within their own
professional expertise and
competence
Pharmacists should not normally
prescribe for themselves, family or
friends except in emergencies
Pharmacists must only prescribe when
they have adequate knowledge of the
patient’s health and medical history
Knowledge Pharmacists must be aware of local
and national clinical guidelines and
take these into account when
prescribing
Practicalities
of prescribing
Relations with
other professionals
prescribers around limitations (what they can prescribe, who they should not prescribe for and the
Pharmacists must make appropriate
patient assessments and only
prescribe when there is a genuine
clinical need
Where pharmacists can prescribe and
dispense they must ensure that these
roles are separated whenever possible
This could be achieved by an accuracy
checking technician or another
pharmacist checking the final
dispensed product
Pharmacists must keep accurate and
comprehensive records of the
consultation with the patient and of the
items that they have prescribed
Pharmacists must refer the patient to
another practitioner when appropriate
Pharmacists must communicate
effectively with other practitioners
involved in the care of the patient
information they must have access to before they
can prescribe), knowledge they should have, communication and the practicalities of combining prescribing and dispensing (Box 16.4).
KEY POINTS
*
Some nurses became the first non-medical
prescribers in 1994
*
Independent prescribers are responsible for
diagnosis and prescribing without reference to
other healthcare professionals
*
Supplementary prescribing is a voluntary
partnership between prescriber a nd patients
which is more beneficial in chronic
conditions
*
Diagnosis is made by an independent prescriber,
then a clinical management plan is agreed
between the independent and supplementary
prescribers
*
The clinical management plan is drawn up for a
specific patient, but it can vary widely in detail and
scope
*
A patient group direction allows provision of named
medicines in specific clinical situations, but not
necessarily to a named patient
*
Pharmacists may have the choice of over the
counter sale, prescribing as part of a minor
ailment scheme or supply through a patient
group direction
*
When recommending over the counter, the
pharmacist is acting as an independent prescriber,
but is restricted to GSL or P medicines
*
Minor ailment schemes are locally agreed and vary
widely
*
In a minor ailment scheme, the pharmacist can
give advice only, or supply, via a prescription or
patient group direction, a prescription only
medicine, or refer the patient to a medical
practitioner
*
A range of factors is known to affect doctor
prescribing. These may also affect pharmacists
*
Applying clinical governance and the RPSGB Code
of Ethics to prescribing is a professional
requirement
161
This page intentionally left blank
Chapter Seventeen
The prescribing process and
evidence-based medicine
Jason Hall
17
STUDY POINTS
*
The stages involved in the prescribing process
*
Evidence-based medicine
Introduction
The prescribing of medicines is the most common
medical intervention in patient care and drug costs
are a major component of NHS expenditure. Ensuring optimum benefits for patients and value for
money for taxpayers and other individuals and organizations paying for health care are priorities. A model
of ‘good prescribing’ has been proposed that has four
aims (Barber 1995). These aims are to: maximize
effectiveness, minimize risks, minimize costs and respect patient choice. Maximizing effectiveness is
about selecting a drug therapy that will achieve its
therapeutic objective in a suitable timescale. Minimizing risks is recognizing that all drug treatments carry
an element of risk of causing harm to the patient and
that selection of the drug should be about managing
the benefits and risks. The cost of therapy should also
be taken into account by the prescriber (see Ch. 19).
Such consideration should go beyond a simple review
of the drug costs to also consider any costs of monitoring treatment such as blood tests, the length of
treatment and any additional items that could be required, such as prescribing an additional drug to protect the gastrointestinal tract from adverse effects
caused by the first drug. Establishing the views of
the patient is a vital part of the process of assessing
the relative importance of the first three aims in this
model. Patients may differ in their views regarding
managing the symptoms of a condition, living with
the consequences of a condition, exposing themselves
to risks of harmful effects and the amount of money
they would be willing or able to pay for treatment. In
addition, patients may wish product selection to take
their lifestyle into account such that the frequency
and route of administration of the selected product
fits in with their daily routine. It is accepted that
‘good prescribing’ involves trade-offs between these
four aims and that this often involves delicate balancing between each of the aims.
The prescribing process
The prescribing process will be considered under five
headings, although there is some overlap between
these and their sequence may not be the same in all
cases. The first is concerned with all the things that
must be in place before a prescriber can start to prescribe, the second with collecting information, the
third with analysing the information and making
the prescribing decision, the fourth with making appropriate records and plans for monitoring the
patients progress; and the last with auditing and evaluating prescribing practice.
Prerequisites
Prescribing can only be carried out by healthcare professionals with appropriate prescribing qualifications
and these will vary depending on the type of prescribing to be carried out. To prescribe prescription only
medicines (POM), either on the NHS or privately, the
prescriber must have successfully completed training
SECTION THREE Pharmacy prescribing and selection of medicines
to allow them to act as a supplementary or an independent prescriber (Department of Health 2006).
The training course consists of a taught element
(around 26 days) and learning in practice (around 12
days), which includes prescribing under the supervision of a medical prescriber. To participate in a minor
ailment scheme and prescribe pharmacy only medicines (P medicines) at NHS expense the pharmacist
will likely have had to complete appropriate accreditation set by the local primary care organization.
Patients who are to receive their prescriptions from
a supplementary prescriber must give informed consent. Patients do not need to sign this informed consent but it is good practice to make a note in the
patient’s medical notes when informed consent was
given. The exact nature of informed consent is difficult to define and it is likely that the input from the
healthcare professional will vary between patients
when obtaining consent. Observation of disputes between patients and physicians regarding whether informed consent was given shows that simply handing
the patient a leaflet does not discharge the physician
from their obligation to obtain informed consent. In
any legal dispute it is up to the courts to decide which
party they believe. However, the disputes that found
in favour of the physician tended to be those where
the physician was able to demonstrate that they had
given the information to the patient because they had
documented the advice they gave in the patient’s
medical records.
Prior to the patient consultation the prescriber
should ensure that they are suitably prepared. Part
of this preparation includes ensuring they have sufficient indemnity insurance that covers their prescribing and that their job description clearly shows that
prescribing is part of their role. Another part of the
preparation is acquiring the appropriate knowledge
and skills (Box 17.1).
Consulting with the patient
Where possible, prescribers should familiarize themselves with the patient’s medical history prior to the
consultation. Obviously this would not be possible in
minor ailment schemes as patients are likely to arrive
without an appointment and their medical notes will
not usually be available to the community pharmacist.
During the consultation, prescribers must take a
full history of the presenting condition and any other
factors such as other conditions the patient has and
any other medications, including over the counter
Box 17.1
Checklist for knowledge and skills required by
pharmacist prescribers
Legal restrictions affecting which medicines
can be prescribed
Independent pharmacists can prescribe any licensed
medicine except controlled drugs and supplementary
prescribers can prescribe any licensed or unlicensed
medicine including controlled drugs provided it has
been specified in the clinical management plan
Professional restrictions affecting which
medicines can be prescribed
It is vital that each prescriber prescribes only within
their own area of competence. Knowing one’s own
limitations is a key skill for a prescriber. In addition,
they must also have an appropriate level of
experience dealing with the condition and it might be
appropriate to refer a patient presenting with a
condition rarely experienced to another prescriber for
assessment and any prescribing if required
Administrative arrangements regarding
payments for the service
The administrative arrangements regarding the
prescribing process must be fully understood. In the
case of minor ailment schemes, these arrangements
could include a description of records that should be
kept and how payment for the service is to be made.
For NHS prescribing, the prescriber should be aware
of the categories of patient that are exempt from NHS
charges and what payments should be made by
those that are not exempt
Patient confidentiality
Pharmacist prescribers must maintain patient
confidentiality and take steps to ensure that no
unauthorized personnel can gain access to patient
medication records by securely storing the data either
via lock and key or via appropriate electronic security
measures such as passwords for data stored
electronically
Ethics
Prescribers should be aware of the good practice
guidance from the Department of Health and the
Royal Pharmaceutical Society’s statements on
prescribing in the Code of Ethics before they start
to prescribe. This guidance addresses prescribers
not prescribing for themselves, not normally
prescribing for members of their family, and also
covers accepting gifts and hospitality for suppliers
Security
Prescribers must be aware of security issues
surrounding prescribing and take steps to minimize
164
The prescribing process and evidence-based medicine CHAPTER 17
the risks. Blank prescription forms could be used by
drug misusers to try and obtain supplies of
prescription medicines for abuse or to sell to others.
Care must therefore be taken to ensure that the forms
are securely stored. Personal security must also be
considered if the prescriber is visiting patients in their
own homes or other locations in the community
Therapeutic management of conditions
A pharmacist’s knowledge and skills required for the
management of a therapeutic area must be up to date
and based upon the best evidence available at the
time. The knowledge should extend to non-drug
approaches to treatment as sometimes these could
be the most appropriate intervention
Other members of the healthcare team
Prescribers should be aware of other professions
they could refer patients to, e.g. general practitioner,
the accident and emergency department in the
hospital, dentists, the community nursing service
(district nurses and health visitors), social services
and self-help groups
medicines and complementary medicines, that the
patient may be taking. It may be necessary to carry
out further investigations such as measuring the
patient’s blood pressure. This information must be
recorded in the patient’s medical notes.
Before any prescribing can take place a diagnosis
must be made. If the pharmacist is acting as a supplementary prescriber, the diagnosis will have been made
by an independent prescriber, but the pharmacist
should interpret the information obtained before
and during the consultation to check that the patient’s
diagnosis remains valid. Independent prescribers must
establish a working diagnosis based upon the information they have gathered on the patient. At this stage it
may be necessary to request laboratory tests such as
urea and electrolytes, red blood cell count and haemoglobin tests to help confirm the working diagnosis.
With increasing complexity of health care and increasing specialization of the roles of healthcare professionals there is a growing need for different
professions to work together. Pharmacists must ensure that they are aware of the different professions
they could call on for support or to refer patients to.
Examples of referrals include the patient’s general
practitioner, the accident and emergency department
in the hospital, dentists, the community nursing service (district nurses and health visitors), social services and self-help groups.
Where patient care is shared between healthcare
professionals there is an obvious need for clear communication links, especially around monitoring and
reviewing the patient’s therapy. Clear communication
links are particularly crucial in supplementary prescribing where two different professions can prescribe
for a patient. There must be a clear description of the
criteria that would require the supplementary prescriber having to refer the patient back to the independent prescriber. Examples of such referrals could
be failure of the patient’s condition to respond to the
therapy outlined in the clinical management plan or
the patient suffering an adverse drug reaction (ADR)
to the prescribed medication. With supplementary
prescribing, both independent and supplementary
prescribers must have access to a common medical
record.
Prescribing decision making
Upon analysis and interpretation of the patient’s
signs, symptoms and laboratory test results, the pharmacist prescriber must consider the treatment
options, including the option of offering no treatment
to the patient. The consideration of therapy options
must include concurrent diseases and medication and
the patient’s lifestyle (would the treatment regime fit
in with the patient’s schedule or would side-effects
of drugs affect their ability to perform their usual
activities).
A key component of this phase is involving
the patient in the decision making in order to achieve
concordance. The prescriber must communicate the
benefits and risks of the different treatment options
to the patient or their carer. The principles of concordance dictate that patients should fully participate in
the decision-making process, and a consultation style
where patients are treated as equals and have the
opportunity to ask questions and to raise any concerns or worries they might have is more likely to
achieve this.
Following selection of the drug and its formulation,
the dosage regime must be determined. The dosage
guidance in the summary of product characteristics,
British National Formulary or local and national clinical guidelines should be used to work out the dosage
to be prescribed. In general, it is recommended that
dosage be started at the lower end of the dosing
schedule and that the dose should be gradually increased until the required therapeutic benefits are
seen while minimizing side-effects. However, there
165
SECTION THREE Pharmacy prescribing and selection of medicines
are many exceptions to this, such as prescribing a
loading dose for certain antibiotics or prescribing
drugs where the therapeutic benefits are not obvious,
such as drugs used in prophylaxis.
The prescriber must also indicate the quantity to
be supplied on the prescription. The quantity to be
supplied will depend upon whether the treatment is
likely to be acute or chronic. If the treatment is acute
then the quantity is likely to be enough for the recommended course of treatment. When determining the
quantity to be supplied for a chronic condition, prescribers should bear in mind how often they would
wish to review the patient, whether the patient has to
pay for the item, the patient’s ability to pay the prescription levy and whether there are any dangers from
accidental or deliberate overdose. In general, smaller
quantities offer the opportunity to review patient’s
therapy more frequently and reduce waste if patients
are unable to take their medicine through the occurrence of troublesome side-effects or ADRs. However,
smaller quantities can cause greater inconvenience as
patients will have to visit their healthcare professional
more frequently and will incur greater expense if they
have to pay for their medication. Smaller quantities
will also increase the prescriber’s workload as they
will have to write more prescriptions.
Recording and monitoring
It is important to realize that the responsibilities of the
prescriber do not end with signing the prescription.
The prescriber must make appropriate records of the
medicine(s) prescribed and any advice given to the
patient in the patient’s medical notes. For paper held
records, the prescriber will obviously have to write
the name of the prescribed item, the formulation, the
strength and the dosage instructions in the notes. In
the case of electronic prescribing the details of what
was prescribed, the date of prescribing and the directions will be stored automatically in the patient’s
records. However, there may be a need to record
additional information such as when the patient
should next be reviewed and the monitoring that is
recommended.
All prescribing should be followed up with some
monitoring although in some cases this may be left to
the patient or carer to do themselves. Monitoring
should address the anticipated benefits from therapy
such as control of the patient’s symptoms and harmful effects such as the patient suffering from adverse
effects. In many situations the patient or their carer
will be given advice regarding what to do should the
beneficial effects not materialize or if the harmful
effects are troublesome. However, there may be
situations where these are not apparent, such as monitoring blood cell counts following administration of a
drug known to affect blood cell formation. These
patients should be informed when they will next need
to have their therapy reviewed.
Prescribers must appreciate any drug can cause an
ADR, but t hat certain drugs are more likely to cause
an ADR. Therefore, they must be aware of the action
required if patients suffer from an ADR. Minor
ADRs that are known to occur with establ ished medicines do not need reporting while serious suspected
and actual ADRs for new and establ ished medicines
and all ADRs for new medicines should be reported
via the yellow card reporting scheme (see Chs 19
and 4 7).
Auditing and evaluating
practice
Like all areas of practice it is important that prescribers reflect upon their practice and use their continuing professional development (CPD) to develop
professionally. Prescribing audits and prescribing
reviews can assist the process of reflection. The availability of prescribing reviews will depend upon the
area of prescribing practice and, to some extent, the
location. The collation and analysis of prescribing data
in secondary care is the responsibility of the trust and
there is great variability in the availability of such data.
All parts of the UK produce prescribing reports for
primary care prescribing although different organizations are responsible for these reports in different
parts of the UK and there will be differences in the
types of report produced. The majority of the reports
are concerned with medical prescribing which is,
perhaps, not surprising considering doctors are responsible for the majority of prescribing activity.
Non-medical prescribing reports are produced locally
by primary care organizations and therefore subject to
greater variation between different localities. Prescribing data include the number of items prescribed
and the cost of prescribing. It should be noted that
these data allow questions for reviewing prescribing
practice to be formulated but very rarely ever provide
answers. There are many reasons why prescribing figures can be skewed one way or the other. These can
make it difficult to make comparisons between practices. Examples of factors affecting prescribing rates
166
The prescribing process and evidence-based medicine CHAPTER 17
include above average numbers of patients living in
residential or nursing care or a practice being located
in an area with a higher prevalence of disease such as a
former coal mining area. Prescribing data do not contain any patient-specific data so it is not possible to
differentiate 10 items prescribed for 10 different
patients and 10 items prescribed for a single patient.
Prescribing data do not contain any drug indications,
which can make it difficult to review the prescribing
of drugs with several indications. There are usually
major differences between the case mix of different
professional groups, which makes comparing prescribing across professional boundaries a particularly
difficult task.
Evidence-based medicine
Evidence-based medicine (EBM) has been described
as ‘a means of closing the gap between research and
everyday practice and ensuring that clinical decisions
are based upon the best available scientific evidence’
(MeReC Bulletin 1995). It allows healthcare professionals to compare the evidence for different
treatment options. This comparison may sound
straightforward but unfortunately the available evidence is frequently of variable quality and different
studies may use different methodology or may measure different aspects of health, which makes comparisons difficult.
The process of EBM involves four stages (Eccles
et al 1998). The first involves identifying the ques-
tion to be answered, such as: ‘Does treatment with
drug X prevent more cardiovascular events than
treatment with drug Y?’ The second stage involves
searching the literature to find studies that have
compared drug X with drug Y. The third stage is a
critical appraisal of the studies that have been identified, which involves making judgments about the
quality of the studies, comparing the evidence supporting drug X with that supporting drug Y and determining whether the balance of evidence favours
onedrugovertheother.Thefinalstageisapplying
the evidence to clinical practice, which could involve
recommending one drug be prescribed by clinicians
rather than the other.
Assessing the quality of the evidence involves
comparing the studies reported in the literature
(see Ch. 2 3).Thereisahierarchyoftypeofstudies
in terms of quality with meta-analysis of more than
one randomized controlled trial at the top, then single randomized controlled trials, then controlled
trials without randomization, then descriptive or
case control studies and finally reports from expert
committees (Eccles et al 1998;seeTable 17.1 for a
description of these terms). A key point to note
concerning the method used in the study is whether
the study was double blind or not (double blind is
where the researcher and th e subjects did not know
which treatments were given to the subjects). The
review of a study should also consider whether there
isapotentialforbiasinthestudybyconsideringwho
funded the study and the af filiation s of the authors.
It is important to review the doses of drugs used as
some studies do not use equivalent doses of drugs,
particularly where one drug is compared with a
Table 17.1 Studies investigating health care
Type of study Description
Meta-analyses A statistical method of combining the results of more than one trial
Double blind randomized
controlled trial (RCT)
RCT A study where one group of subjects is randomly assigned to receive one treatment and the other
Case control studies A study that compares one group of patients with another
Cohort studies A study that follows the progress of a group of patients (a cohort) and compares their progress to
Expert opinion A report from an expert committee or opinions expressed by a respected group of experts
A study where one group of subjects is randomly assigned to receive one treatment and the
other group to receive an alternative treatment or placebo. Double blind is where neither the
researchers nor the subjects are aware of which group they have been assigned to
group to receive an alternative treatment or placebo
the characteristics of the group members
167
SECTION THREE Pharmacy prescribing and selection of medicines
competitor’sdrug.Thereviewersshouldconsider
whether t he study used healthy volunteers or patients suffering from the condition and whether
the demographic profile of the subjects was similar
to the general population. Generally, the larger the
study, in terms of the number of subjects included,
the higher the quality of the study. However, the
number of subjects needed to show an effect is dependent on the magnitude of the effect, with larger
numbers needed to demonstrate smaller differences
between the different arms of the study. The length
of the study is another important consideration. This
should be related to how the drug will be used in
practice as the benefits reported in a study lasting
10 days would have more relevance to a drug used
to treat acute short-term conditions compared to
long-term chronic conditions where the benefits
could wear off after the study ends. The review
should consider the endpoint reported in the study
(what was measured in the study) and whether
theendpointwasthesameastheintendedoutcome
(e.g. the intended outcome of a treatment in a study
could be a reduction in the incidence of cardiovascular events but the endpoint used in the study
mightjustaddressoneriskfactorforcardiovascular
events).
Information sources
The evolution of modern medicines and appliances
has resulted in a tremendous increase in the range of
products available on prescription and a corresponding increase in the amount of information available
to support their use. This vast array of information
originates from many sources including the pharmaceutical industry, academic institutions, professional
bodies, government agencies and patient groups.
Much of this information is aimed at prescribers and
other professional groups, but, with the increased
availability of this information through advances in
information technology and the upsurge of public
demand, many patients also have greater access to
information about medicines. With such a variety of
sources all competing for the attention of the prescriber there is a danger that they could be overloaded
with information of variable quality and which is
potentially conflicting.
Reports of studies published in the literature can
be obtained by using online resources and archives
such as Medline, Embase or PubMed, although it
is likely that most searches will result in large numbers
of hits and reviewing the quality of such a large number of papers will be very time-consuming. Alternatively, there are several sources of evidence-based
medicine reviews. The Cochrane Library is a collection of databases that contain evidence-based reviews
and is available through the National Electronic
Library for Health and University Libraries. Clinical
Evidence from the BMJ Publishing Group provides a
summary of the evidence available for managing a
wide variety of conditions and includes an assessment
of the quality of the evidence (see Ch. 23).
Guidelines
There has been a recent proliferation in the number of
guidelines produced in developed countries to assist
practitioners in a wide variety of clinical roles. They
have been defined as ‘recommendations on the appropriate treatment and care of people with specific
diseases and conditions’ (National Institute for
Health and Clinical Excellence 2008). However, it
should be noted that the foundations on which guidelines are based could range from guidance based on
good quality evidence to those based upon expert
opinion. The quality of guidelines can also vary and
prescribers must decide whether a guideline is suitable for use in their practice. In addition, there are
few, if any, guidelines that can provide guidance that is
appropriate for 100% of patients. Prescribers should
not follow guidelines blindly but consider in which
situations the guideline should be used and those
when it should not. If a prescriber decides to deliberately deviate from a guideline, they should document
their reasons for deviation in the patient’s medical
notes.
The National Institute for Health and Clinical Excellence (NICE) is an independent organization responsible for providing ‘national guidance on the
promotion of good health and the prevention and
treatment of ill health’ (NICE 2008). NICE provides
guidance to support the management of a wide range
of clinical conditions. The Scottish Intercollegiate
Guidelines Network (SIGN) produces evidencebased clinical guidelines for use by people working
in the health service and for patients.
Computerized decision support
Software is available that can assist the healthcare
professional with diagnosis and prescribing. Relevant
patient information such as the age, sex, symptoms
168