CLINICAL EPIDEMIOLOGY Applying Science to the Art of Nurse-Midwifeq

A nurse-midwife

colleasue often re-

fen to herself

as %I

e&t

in a sc~

entiffc world”;

no doubt many CNMs

practices. As we learned m our ba-

studies.

sk

pro-

these articles es well. Many clinicians

man-

assume that if e research paper is

nurse-midwifery

grams.

efficient

education

and effective

but similar cave&

apply to

would approve. Attractive as this pic-

agement must be anchored in a solid

published in a peer-reviewed pumal,

ture may be. it reflects a common

theoretical

the results can be taken at face vaiue.

misperception tha! how we practice es clinicians can somehow be di-

tially means it must be based on good research.

vorced from

For most purposes, reading the research

this of

ory and statistics that go with it. can

Doubtless

ot c!i”iziens

be left to the researchers. Of couree.

would

we are grateful

as findins time to keep uo with the liter&& Few of us consider other more selious limitations. Texts and

scientific

melhod.

Re-

search, it would seem, and all the the-

search&who

for good CNM

re-

document the benefits

of midwifery care, but beyond that, who needs it? The a-r is simple: We all do.

foundation.

This

the majority

identify

their bigg&t

essen-

means others. problem

However.

a review

of original

re

search published I” fiw leading medical journals during a one-month period in 1980 resulted in the relation of 57%

of the aticks

!or failing to

meet specified requirements

for-s+

entific proof and clinical apphcability (1). Although editors and peer wviewen have undoubtedly become

review articles. for example. reflect anneone eke’s eualuation and syn-

more d&m

Research, and the principles that pro-

thesis of the literature.

decade. one need only read the cur-

duce gocd research, play a vital role in clinical practice. As cllniclans. we

the authois

want to make the right diagnosis and

sented; otherwise,

prevent adverse outcornee. We want to achieve whatever therapeutic ben-

a” adequate and unbiaxd done. Editors and retiewezs

efits me possible and avoid subjecting

guidelines to weed out the obviously

our patients to unnecessary InPave”-

inadequate

confident

If we recognize

reputation. in

the

we may be

conclusions

pre-

we must kuet that

manusrri@s.

lob was &I have Addition2

sophisticated aboui research and methodology over the past

re”t “Letters

reviewers with expertise in the subject

rely on research to guide us in these

may be asked to evaluate .whether

u&ion

efforts. Studies identifying risk factors for adverse outcomes are the basis of

the author

sugg&im

screening and prevention New

modalities

treatment

of

become

mmmonplace

when clinical research certifies benefits. Newer shxiies

and their

may point to

the lack of benefit of certain standard

qtiitycare of

based on thoughtful pertinent

that

‘we

research?

evilThe

kam enough about

sound research methodology to ciitique “w lilemture ours4vrs is birund

programs.

diagnosis

columns

journals to rec.

cfans to do if they want to provide

lions if no benefit is to be gained. We

has cited all of the oeti-

to the Editor”

of these same me&al

ognize that widely varying opmtons about the merits of research findings remain the norm. What then are conscientious clinic

the

authois

bpinionsw and

conclu-

sions may differ from those we would

to produce groans. After all. !he iast thing buy CNMs need is someone

draw ior our own patients.

telling them the9 should be doi”g more

We could decide to accept only the results and conclueions of the original

than they already are. Eut in fact. this is not the enormous

task it might ep-

It is notnecessey to learn

pear.

enou9h to do raeerch;

one only need

clinical practice. based on a synthesis

but also in eveluating all clinical man-

of all the information.

agement

In short,

process is identical

the lack of it). We do something

ready do on e daily basis. All we need

very

similar every day es clinicians when re

855855 ibe status of pregnancy or

to what

the

know enough to recognize quality (or

we al-

is to redefine the indlvldual

steps of

this

researrh

process

in

terms

of

Fletcher et al (3) have out-

lined several observations foundation Most

of the time. the diagnosis,

prognosis,

and results of an inter-

labor to be assured of normalcy, and

methodology.

recognize when there are deviations

cess becomes one of assessing

from that normal process

status of e research report for s&n-

dividual patient; they thus should

tiftc validity

be expressed as probabilities.

As studenk, we practiced this nurse midwifay

management

painstaking

detail,

process

thinking

in

of both

normal and abnormal reasons for obsecretions, complaints. da9noses.

Ftnally,

meantfromthe

of the individual yeas.

are uncertain

We judge drawing

from the norm. The roleof research in clinicalmac-

for an in-

these probabilities

by

on past experience with

groups of similar patients. These past experiences are drawn

articles are reshelved.

Critical evalu-

from people who are free to do as

we de-

atton of the literature

shouid

they please, cared for by clinicians

perspective

patient.

and rec-

there are deviations

vention

lice does not end when the j&ml

cided what all of these facts and orobabilities

(“normalcy”)

when

the

al-

or symptoms.

We collected data and weighed ternative

ognizing

The management pro-

that are the

of this ditipltne:

Over

the

the process has become inter-

be the

basis for our decisions about whether or how we apply the results

of re-

search to clinical practice. In feet. the profess

with differing skills and prejudices. Tnus

these experiences

are sub-

ject to a variety of influences

of assesising scientific validity

that

can dktort the true Mture of evenis.

nalized and automatic. and it is often

can and should form the basis for all

and may mislead our conclusions.

accomplished

cilnical management decisions. Sack-

To

on il nearly

intuil;ie

level. Some of us would even find it

ett et al I21 distinuuish

difficult now to describe it in step-by-

art of cll&~l

step detail. Consider the clinician who

beliefs, judgments,

sees a pregnant worna,,

cannd

for the first

time and finds that, although the 9estational age is 36 weeks, the fundal height ineasures zsessments

32 cm. A series of

inform&n

correct? Is the

about

gestational

explain)

and Intuitions

edge, lo+,

aqe

we know that good cli-

stress the importance that scientific

go cm to

of recognizing

methods

should

sop-

urong? What is the probability that there is a problem such es intieuter-

pert the er! of clinical mnwgement, methods that have been codified in

ine growth retardation: Is this woman at risk? Are there other factors, such

recent years under the rubric of “dinical epidemiology.”

as trenweree

lie or .a well-engaged

head, that can explain

the discrep-

Epidemiologists

study

bution and determinants

the

distri-

of disease in

ancy? What has the pattern of growth

human

been? In the end, the clinician will make a management decision for this

discipline has been concerned about the best ways to address these issues. Paticular attention ts paid to how the

woman based on e synthesis the information.

of all

is not much different. variables

measured

populations.

validity

The process of cridquing research Are the stodv in a way

that

es opposed to highly structured experiments.

of epidemiologic

is the information

phasize awaremss can be intioduced

in the study? Are

years, this

of research is affected when

makes sense? How valid and reliable there other factors that could exolain

For

It is conducted in human papulations, oratory

The

living human beings. Clinicians studied

the1 tbii

is true? with

1s this

other

re-

tions

epidemtol&y

of these

em-

of the biases that in studies of free-

probability

consistent

lab-

principles

methodology

this apparent association? What i:s the finding

these misleading

ef-

n~ust be

scientific

prtnci-

pies.

one

and prior experience we

can explalnj;

miti9ate

fects, clinical observations based on sound

and the science of

clinical care (derived from the knowl-

nicians practice both. They

!ollows that observation.

Is the .neasurement

hehveen the

care-(derived from the

saw

principles

who

applica-

in clinical

Clinical qxdemlolosy cerned with delineating

then is conthese princi-

ples, out of respect for the need to gather

the

i. at

“best

possible

evidence

the effectiveness and effidency

of. [clinical caxl the increasing complexity

atatime

of of what we

might be able to do for patients, end an increasing recognition that we should not do manv thinas. and cannot do all” (4). _

._

This phtlosoohu appeal to CNMs.

should certainlo Whether we a&

reading a research report,

screening

a patient for risk, or deciding whether an intervention is indicated, we want the best possible patient’s

interests

evidence that the are being served.

In this spirit, the Journal Mldwtfey

is be&&g

“Clinical R-h

ofNurse-

a new mlumn, Semkw,”

that will

try to dissect and explain epidemiologic methods We till devoted

for the buey clinician.

begin with a sertes of tides to crltlcal evaluation

research literature.

Although

of the techni-

search? Finefly, the reviewer will make

practice es well, not only in clarifying

cal terms and statistical jar9on are in-

a decision about the scientific

the role research conclusions should play in scien&aUy based chd care,

evitable, we will ty

of the piper

220

ard

merit

its applicability

to

Joemet of NurseMidwifely

a manageable

.

to keep them to

minimum.

Clinically

Vol. 37. No. A JulylAuguet

1992

oricnted example< u,iU be used to il-

Equally valuable may be an ability to

lustmte

recognize flaws in studies

points

wii~~ the

hope

that

readers will bettc, xecognize how research methods,

gwd

affect lnterpretat~on Consciousapplication “mana4ement

and bad, can

tield

part

literature

forcefully

against

application.

of a broader

valuation

Clini-

their

Recognizing of research is

focus on cntical

of clinical care. future col-

umns will discuss the applications

cians will be able to reduce the e;, x-

clinical epidemiology

mow volume of research literature to

wifely

a smaller subset of well-done siudies

will be interesting

that have clinical importance. Only ihesc need affect practice decisions.

REFERENCES

of “fash-

in order to ar-

that critical evaluatian

to the ob-

benefits.

more

widespread

of this research

process”

several

gue

of the findings.

stetricl&natal or other should

ionable” interventions,

of

to nurse-mid-

2. sacken DL, Haynes RB, T”g.vvell P Clinical epidemiology: a basic sciencefor clinical medicine.l ix 3. Fletcher RH. Fletcher SW. Wagner EH. Clitica: eoidemlolcw: the exsentiah.

practice. We hope the series and beneficial.

Patricia Aiktns Murphy.

crw.

~5

Associate Editor

_

_

“MtdwlvebHoar the Heartbeat of the !htwe” lntemattonal ConfederatIon of Midwives 23rd Trknniaf Conmess May 9-14. 1993 Vancouver, British Columbia. Canada For Frvther Information Contact: Congress SecretaiaUlCM Planning Committee c/oVenue West Conference Management kke. # 645.735 Water Street Vancouver. BC, Canada V6B 5CB Tel: (604) 631.3226 Fax: (604) 631-2503

humal of Nurse-Midwifery.

“a,. 37, No. 4. JuiyiAugti 1992