copy of variables and an operational definition (19 maret)

7/27/2019 Copy of Variables and an Operational Definition (19 Maret)

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A Variable & An Operational Definition :

The Nursing Research Perspective

By :

Kumboyono

Department of Nursing

Medical Faculty Brawijaya University

April, 2004


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Class Objectives :

After completing this class, the student

should be able to :

Exlpain about the variable of nursing research

Explain about the operational definition of

variable


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Introduction

An important part of critiquing research is

determining whether the author is clear and

consistent regarding :

How the concepts in the framework are

used in the design of the study

How the concepts are operationalizedinto variables


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Introduction

Quantitative studies

Variables

Qualitative studies

Topics

phenomena

Terms used to refer to the concepts that are

being investigated :


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Introduction

We are always thinking in constructs,concepts and variables.. It helps us

organize and order the world around us.We think of animals, then fish, then shark.

This represents :

a construct (animals)

a concept (fish)

a variable (shark)


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Constructs, Concepts, Variables

Construct : a concepts with a general meaning

within a conceptual framework (e.g. :

emotional responses)

Concept : term that abstractly describes and

names an object or phenomenon (e.g. : anxiety)

Variable : precise, well-defined concepts thatwill be measured in research study (e.g. :

response to questionnaire anxiety levels)


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Constructs

A mental image of a phenomenon

An idea or construct in the mind about thingor an action

a cluster of characteristics that describesthe concept

A construct is broader and more abstract

than a conceptconstruct : quality of life

concepts : satisfaction with self,

happiness


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Concepts

Range from being very abstract to beingvery concrete

abstract : anxiety

concrete : body temperature Concepts are at a higher level of abstraction

than a variable

concept : dyspneavariable : self-report of dyspnea,

respiratory rate


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Variables

A variable is a characteristic, a trait,

property, or a condition

A variable is a characteristic being

measured that varies among the persons,

places, or objects being studied.

variables are measurable characteristics

that can take on different values


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Examples :

Construct Concept Variable

Symptomdistress

Pain

Vomiting

Response toquestionanaire

behavioral cues

Amount of

vomiting


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Examples :

Construct Concept Variable

CardiovascularHealth

Hypertension

Hypercholesterolemeia

Blood pressure

Lipid levels


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Tipe Variabel

1. Berdasarkan jumlah :

Variabel univariat

Variabel bivariat

Variabel multivariat

Bagaimana pengaruh pelaksanaan standar praktek

keperawatan dengan insidensi komplikasi,

penurunan masa rawat inap, penghematan biaya ?


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2. Sifat hubungan

Variabel dependentVariabel independent

Variabel intervening

Variabel extraneous

Adakah pengaruh terapi kompres hangat denganpenurunan suhu tubuh pasien typoid ?

Is there a correlation between the number of stressreported by nurses in an intensive care unit andnurses desire to leave employment )?


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Hubungan antara usia dan kecelakaan kerja

Dapatkah penggunaan alat pelindung yangberbeda-beda menjelaskan antara hubunganusia dengan kecelakaan kerja ? (intervening

variable) Apakah pengaruh jenis-jenis pekerjaan ?

(confounding variable)

Apakah pekerja lansia cenderung mengalamikecelakaan kerja pada tahun-tahun pertama ?(modifier variable)


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Pembagian vairabel berdasarkan sifat

hubungan penting untuk :

Menggambarkan kerangka konsep

Mengembangkan kerangka analisis

Variabel dipilih atas dasar relevansinya

dengan pertanyaan penelitian, tujuanpenelitian dan hypotesis penelitian


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Type Variabel

3. Skala pengukuran variabel

Variabel nominal

Variabel ordinal

Vatiabel interval

Variabel rasio

Variabel Kategorikal /

Kualitatif

Variabel Kontinyu /

Kuantitatif


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Categorical variables

Categor ical var iablesare those that are made to fit

into a few discrete categories:

Age could be specified as a categorical variable, e.g.,1=young (31 y.o.).

Smoking habit could be specified as a categorical

variable, e.g., 1=non smoker; 2=smoker.


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Continuous variables

Continuous var iablesare those that are specified

as a range of values along a continuum:

Age could be specified as a continuous variable, e.g.,any year of life ranging over the life of the subject.

Smoking habit could be specified as a continuous

variable, e.g., pkgs/day x 365 x #yrs


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Nominal

Lowest of the four levels of measurement

Categories that are not more or less but aredifferent from one another in some way

Mutually exclusive & exhaustive categories

E.g. : gender, ethnic background


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Ordinal

Categories must be exclusive and

exhaustive

Quantity of the attribute can be identified.

It cannot be demonstrated that the intervals

are equal: unequal intervals


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Ordinal

Many scales in nursing research are ordinal

scales

Some may be referred to as metric ordinalscales are are treated as interval scales if the

intervals are considered to have some

evenness.


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How often do you feel in control

of your life?

(1) Never

(2) Seldom

(3) Often (4) Almost always

Rating Scale


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SCALING

Rating Scales--ordered series of categories

of a variable based on an underlying

continuum.Never, Sometimes, Often, Frequently

Likert Scale

Strongly agree, agree, neutral, disagree,strongly disagree


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INTERVAL SCALE

In this case, the distance between these

ordered category values are equal

because there is some accepted

physical unit of measurement. In the

Fahrenheit thermometer, mercury rises

in equal intervals called degrees.


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INTERVAL SCALE CONT..

However, the zero point is arbitrary,

chosen because Daniel Fahrenheit, the

inventor, decided that zero point on

this scale would be 32 degree below

the freezing point of water.


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INTERVAL SCALE CONT..

Because the units are in equal

intervals, it is possible to add and

subtract across an interval scale.

You can say that 1000 F is warmer than

50

0

, but you cannot say that 100

0

F istwice as hot as 500 F.


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Highest for measurement

Continuum of values

Absolute zero point

Weight, height, volume

Ratio


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Pembagian variabel berdasarkan skalapengukurannya dikembangkan sebagai

bahan pertimbangan dalam mengkaji statusmetode analisis data

Setiap skala variabel yang berbedamempunyai konsekuensi sifat analisisteknik analisis yang berbeda.


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Latihan :

1.Status ISPA

2.Suhu Badan

3.Cakupan imunisasi4.Tingkat pendidikan

5.Prevalensi TB Paru

6.BOR

7. LOS

8. Jenis Malaria

9. Biaya pelayanankesehatan

10. Status imunisasi

11. Status gizi


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Latihan :

12. Status sosial

ekonomi

13. Persepsi terhadapDHF

14. Status ANC

15. Kadar HB

16. Jenis Hepatitis

17. Morbiditas penyakit

diare

18. Cara pembayaran

pelayanan kesehatan

19. Paritas20. Jumlah peneriamaan

tablet besi

21. Pengetahuan ibu

tentang larutan gula

garam


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Conceptual Definition:

The abstract meaning of a variable

that usually is based on theory.

Operational Definition:

A way of defining a variable that

makes it measurable or manipulatable

in the real world.

Operationalizing Research Variables


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An operational definition

An operational def ini tionis how the researcher definesthe variable in measurable terms.

Given the mechanical means thus far invented to operationalizethe concept of diastolic blood pressure, different methods maynecessarily distort the definition, and the results:

Will dBP be defined by auscultation as the 4th or 5th Korotkoff sound?, or

Will dBP be defined by the nadir of the direct arterial pressure wavesdicrotic notch?, or

Will dBP be defined by the arterial pressure at which ECG indicates peakventricular electrical repolarization?


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Heart rate is a concept defined in intellectual terms as the frequency that

cardiac contractile cycles are recurring one after another.

Researchers can come up with different ways to measure heart rate, among

which some ways are more sophisticated than others : Palpation of a peripheral arterial pulse [feel]

Auscultation or Doppler [listen]

Visual by echocardiographic observation [look]

ECG [indirect]

Photomagnetic oscillations [indirect]

the operational definition of heart rate would have to be modified if it was

important to account for observations in which the number of atrial and

ventricular contractile cycles per unit of time did not correspond.


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Is there such a thing as love?, or happiness? [love and

happiness are concepts that virtually everyone can

identify, but cant agree on how to measure] Can the degree to which people love other people

change?, and does peoples happiness vary and function

as the cause or result of circumstances? [if yes, then they

are variables]

If you want to study them quantitatively, you will have

to operationalize love and happiness in measurable

terms. Any ideas for how to go about doing that?


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Cara mengoperasionalisasikan variabel :

Hindari istilah dalam kamus / tekstual

Mendefinisikan dalam makna kontekstual

Hindari pernyataan dalam bentuk negatif

Apa yang didefinisikan tidak boleh masuk

dalam definisi

Tidak dinyatakan dalam bahasa yang kabur

(ambigous)


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Alasan Mendefinisikan Variabel Penelitian

1. Agar tidak menimbulkan kekaburan fokus

penelitian dan menghilangkan salah penafsiran

terhadap obyek yang menjadi fokus penelitian2. Mempersempit fokus target populasi dan

wilayah penelitian

3. Memudahkan pembuatan instrumen penelitian

4. Memberi makna kontekstual terhadap masalah

yang menjadi fokus


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Summary

Construct

Concepts

Variables

Operational Definition

Indicators

Measurement

copy of variables and an operational definition (19 maret)

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