CHAPTER III RESEARCH METHODOLOGY

CHAPTER III
RESEARCH METHODOLOGY
A cross-sectional study design was used in order to determine the level of
job stress, role conflict, role ambiguity, and job satisfaction; investigate the
relationships between job stress, role conflict, role ambiguity and job satisfaction; and
examine the predictive effects of job stress, role conflict and role ambiguity on job
satisfaction. Study setting, population and sample, sampling method, instruments, data
collection procedures, ethical consideration and data analysis are presented in this
chapter.
Research design
A cross-sectional study design was used to accomplish the purposes of this
study.
Setting
This study was conducted in the Thai Nguyen provincial general hospitals.
These hospitals are public hospitals, including the A hospital, the C hospital and the
Gang Thep hospital. They are at the secondary care level in health care system, and
are quite similar about organizational structure and policies, but only differently about
total number of staffs, and number of the beds. They were managed under the
jurisdiction of the Provincial Department of Health in Thai Nguyen Province. There
are about 20-24 functional department in each hospital. Total staff nurses have about
150-200 employees. Total of the beds have about over 300-350 (Department of
Planning and Investment, 2010). They provide to treat for outpatients and inpatients
with all kinds of disease, illness and injury (Department of Health, 2009).
Population and sample
Population: the target population for this study consists of 239 staff nurses
working in three clinical units (medical unit, surgical unit, and intensive care unit
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[ICU]) of three provincial general hospitals (the A hospital, the C hospital, the Gang
Thep hospital) in Thai Nguyen province, Vietnam. The population is shown in table 1.
Table 1 The detail of population in Thai Nguyen provincial hospitals
Staff nurses of three units
Hospital
Population
Medical
Surgical
ICU
A hospital
82
40
30
12
C hospital
83
33
35
15
Gang Thep hospital
74
35
25
14
239
108
90
41
Total
Sample was selected from three clinical units (medical unit, surgical unit,
and ICU) in three Thai Nguyen Provincial General Hospitals (A hospital, C hospital,
Gang Thep hospital) from September through October, 2010. The participants are
officials, they directly provide patient care. Those nurses have met the eligibility
criteria are as follows:
Inclusion criteria
1. Currently working full time in the three clinical units (medical unit,
surgical unit, and intensive care unit).
2. Have been working as a nurse for at least 09 months after recruited.
3. Providing direct patient care.
4. Willing to participate in the study
Exclusion criteria
1. Head nurses.
2. The director nurse.
Full time employees are used due to potentially different stress experienced
by both novice time and main working time. The 9 months are chosen because the
respondents were well-oriented to the organization, and passed the initial stress of
working in a new environment. Nurses in management positions are excluded because
there are differences in stressors related to job responsibilities.
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Sample size: Yamane (1973) provides a formula to calculate sample sizes
with a 95 % confidence level and e = .05. When know size of population the sample
size was determined based on the formula as follows:
N
n=
1 + N(e)2
n = sample size
N = population size
e = level of precision
The values were set for formula:
N = 239
e = 0.05
239
n=
1 + 239(0.05)
2
= 150
Therefore, the sample size was 150 nursing staffs.
Sampling technique
This study was applied the multistage sampling technique to determine the
number of participants following step.
1. The first step was applied the purposive sampling technique to determine
the hospitals in this study. The secondary care level of hospitals in Thai Nguyen
province is classified into 3 public health facilities, and 1 military health facility.
There is a difference between public health facilities and military health facility. The
public health facilities provide medical services for large population and all social
strata. In contrast, the military health facility serves only to specific groups. The
researcher selected 3 provincial hospitals from the public health facilities to obtain
representative samples.
2. The second step was applied the stratified random sampling technique to
determine 150 nursing staffs from the 3 provincial hospitals at different hospitals. The
researcher calculated sample size by applying the formula of Cochran (1977). The
numbers of participant in each hospital are detailed in Table 2.
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Nh*n
nh =
N
nh =
Sample in each hospital
Nh =
Population of staff nurses in each hospital
N
Population (N = 239)
=
n =
Sample size (n = 150)
Table 2 Population and sample size of subjects from different hospitals in the three
Thai Nguyen provincial hospitals
Hospital
Population
Sample of hospital
A hospital
82
52
C hospital
83
52
Gang Thep hospital
74
46
Total
239
150
3. The third step was applied the quota sampling technique to achieve
appropriate sample representation at different units. The researcher calculated sample
size for the staff nurses by using the formula of Cochran (1977). The numbers of
participant in each unit are detailed in Table 3.
Table 3 Number of subjects from each of clinical units
Hospital
Popu.
Samp.
Popu.
Samp.
Popu.
Samp.
Med
Med
Sur
Sur
ICU
ICU
A hospital
40
25
30
19
12
8
C hospital
33
21
35
22
15
9
Gang Thep hospital
35
22
25
15
14
9
Total
68
56
26
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4. The fourth step, the participants were selected by using a simple random
sampling technique. The researcher met the director nurse of each hospital to get the
list name of nursing staff, and then selected participant by using simple random
sampling technique. The name of staff nurses were established the lists on papers with
each unit of each hospital. Each name was ordered a number. Number order in each of
the lists was sorted in ascending numerical order starting with 01. And then, the
researcher wrote one numerical label on a small piece of paper, number of pieces of
paper are consistent with the number of staff nurses of each unit, after that, put all of
them in one box and mix well. At the final, the researcher picked up the random one
piece at the time, subject who assigned number was matched with the random
number, this process continues until the desired sample size has been reached.
Instrumentations
Questionnaires
This study used the self - administrated questionnaires to collect nurse
opinions comprising of 4 sections including the Demographic Questionnaire, the
Expanded Nursing Stress Scale, the Role Conflict and Ambiguity Scale and the Job
Satisfaction Survey.
Section 1: Demographic questionnaire
The demographic data questionnaire was constructed by the researcher. It
was designed to obtain information regarding: age; gender; marital status; number of
children, educational level; name of hospital; working units; years of working in
nursing profession; and years of working in the current unit; income; number of
patient per shift. It includes 12 items (Appendix 6).
Section 2: Expanded nursing stress scale
Expanded Nursing Stress Scale (ENSS) was used to measure job stress.
A final version ENSS was developed by French and her colleagues in 1995
(French et al., 2000). ENSS using in this study contains 54 items in eight subscales:
1) Death and Dying with seven items, 2) Conflict with Physicians with five items, 3)
Inadequate Emotional Preparation with three items, 4) Problems Relating to Peers
with six items, 5) Problems Relating to Supervisors with seven items, 6) Work Load
with nine items, 7) Uncertainty Concerning Treatment with nine items, and 8) Patients
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and their Families with six items (French et al., 2000). Discrimination subscale with
three items was not use in this study, because the difference about the cross - culture,
and it is not appropriate for measuring.
Internal consistency reliability was assessed by using Cronbach’s coefficient
alpha. The whole ENSS demonstrated the reliability (α = .96) (French et al., 2000).
The current study obtained reliability to be 0.94.
The 54 items were ranked on a 4-point Likert response scale from 1 - never
stressful to 4 - extremely stressful. The total score ranged from 54-216. Responses are
summed and divided by 4 to provide a mean score. The high score means higher level
of job stress. Responses were some and divide by 3 to provide a mean score. Higher
scores indicate the high level of job stress.
Score transformation: the highest mean score was 4 and lowest mean score
was 1. Dividing the result of highest mean score minus the lowest mean score by 3
gives an interval of 1 (Polit & Hungler, 1999). The written permission was obtained
from the author to use this instrument.
Table 4 Scales of ENSS and item number (French et al., 2000)
Subscales
Item numbers
Death and Dying
1,8,15,24,34,44, and 50
Conflict with physicians
2, 9, 25, 35, and 45
Inadequate emotional preparation
3, 10, and 17
Problems relating to peers
4, 11, 18, 19, 20, and 47
Problems relating to supervisors
5, 27, 28, 37, 43, 46, and 51
Workload
12, 21, 29, 38, 39, 42, 48, 52, and 54
Uncertainty concerning treatment
6, 13, 16, 22, 26, 30, 33, 36, and 40
Patients and their families
7, 14, 23, 31, 32, 41, 49, and 53
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Table 5 Interpretation of job stress (Polit & Hungler, 1999)
Mean Score
Level of job stress
1.00 – <2.00
Low job stress
2.00 – 3.00
Moderate job stress
>3.00 – 4.00
High job stress
Section 3: Role ambiguity and role conflict scale
Role stress was measured by translated Role Conflict and Ambiguity Scale
(RCAS) (Appendix. 4). Role conflict and Ambiguity scale was developed by Rizzo
and his colleagues in 1970 (Rizzo et al., 1970). It consists of 14 items in 2 subscales:
role conflict with 8 items, and role ambiguity with 6 items.
Lu et al. (2007) reported Cronbach’s alphas of 0.82 for role conflict, and
0.80 for role ambiguity. In the current study, internal consistency coefficient alpha
was 0.80 for total scale.
Each item was rated on five-point Likert scale ranging from 1 - never to
5- very often and the total scale ranged from 14-70. Tunc and Kutanis (2009) have
noticed six items for role ambiguity should be reverse scored before summing the
score. Responses are summed and divided by 5 to provide a mean score. Higher
scores represent higher level of role stress.
Score transformation: the highest mean score was 5 and lowest mean score
was 1. Dividing the result of the mean score minus the lowest mean score by 3 gives
an interval of 1.33 (Polit & Hungler, 1999).
Table 6 Interpretation of role stress (Polit & Hungler, 1999)
Mean Score
Level of role stress
1.00 – < 2.33
Low role stress
2.33 – 3.67
Moderate role stress
> 3.67 – 5.00
High role stress
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Section 4: Job satisfaction survey (JSS)
The translated of Job Satisfaction Survey (JSS) was used to measure job
satisfaction (Appendix. 6). The version of Job Satisfaction Survey was developed by
Spector in 1994 (Spector, 1997). The questionnaire consists of 36 items, it is
separated nine facets of job satisfaction. Those facets are 1) pay and pay rises, 2)
promotional opportunities, 3) fringe benefits, 4) contingent reward (appreciation and
recognition), 5) supervision (the person’s immediate boss), 6) coworker, 7) nature of
work (type of work done), 8) communication within the organization and 9) operating
procedures (rules and procedures) to assess employee attitudes about the job and
aspects of the job. Each aspect was assessed with 4 items, and the total score is
computed from all items. A summated rating scale was used, each items is rated on
six-point Likert scale ranging from 1- Disagree very much to 6-Agree very much and
the total score ranged from 36-216. The JSS has some of its items written in positive
and negative directions. The negative worded statements have to be reverse scored
before summing the score. The level of job satisfaction as measured by JSS, the
higher the mean score, the higher the level of job satisfaction. Spector (1997) reported
reliability (coefficient alpha) of the JSS ranging from 0.66 to 0.91 (Spector, 1997).
Norbu (2010) reported reliability to be 0.90. In this study, Cronbach’s alpha for the
total score was 0.80. The written permission was requested from the author to use his
instrument. Below are reliability results on 9 facets of job satisfaction (Spector, 1997).
Table 7 Scale of Job Satisfaction Survey, descriptions and item number (Spector,
1997).
Facets
Alpha
Description
Item number
Pay
.75
Pay and pay raises
1, 10r, 19r, 28
Promotion
.73
Promotion opportunities
2r, 11, 20, 33
Supervision
.82
The person’s immediate supervisor
3,12r, 21r, 30
Fringe benefits
.73
Fringe benefits
4r,13, 22, 29r
Contingent
.76
(not necessarily monetary) given
5,14r, 23r, 32r
rewards
for good performance
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Table 7 (Continue)
Facets
Alpha
Operating
.62
conditions
Description
Item number
Satisfaction with rules and
6r, 15, 24r, 31r
procedures
Coworkers
.60
Satisfaction with coworkers
7, 16r, 25, 34r
Nature of Work
.78
Satisfaction with the type of work
8r,17, 27, 35
done
Communication
.71
Satisfaction with communication
9,18r, 26r, 36r
within the organization
Total
.91
Total of all facets
NOTE: followed by “r” should be reverse scored.
Table 8 The JSS scoring of responses to the items of the scale
Responses
Positive items
Negative items
Disagree strongly
1
6
Disagree moderately
2
5
Disagree slightly
3
4
Agree slightly
4
3
Agree moderately
5
2
Agree strongly
6
1
Table 9 Interpretation of job satisfaction (Spector, 2007)
Mean score
Level of job satisfaction
1.00-2.99
Low
3.00-4.00
Moderate
4.01-6.00
High
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Translations, validity and reliability of instrument
Instrument translation
The original instruments using for this study are English version, hence,
these instruments were translated into Vietnamese version. The translation and backtranslation method used a combination and modified of Brislin’s back-translation
model and a committee approach (Brislin, 1970; Lu et al., 2006).
The specific translation procedures were as follows:
Step 1. Two independent bilingual experts, including 1 bilingual researcher
aware of the objective of the questionnaire and 1 other bilingual person without any
knowledge of the instrument (professional translator) translated the instruments from
English into Vietnamese.
Step 2. The 2 translators synthesized the results of the translation by
consensus. The researcher was observed and recorded a Vietnamese version.
Step 3. The synthesis of the two translations was independently translated
back into English again by 2 different bilingual persons including 1
English teacher and 1 health specialized translator. And then, they synthesized and
recorded the result of the back-translation by consensus.
Step 4. The panel of three experts including 1 psychologist, 2 nursing
administrator were the bilingual experts, as well as the experts in healthcare
management compared the original English version and the back-translation version
with the various translations and developed the prefinal version by consensus. The
role of expert committee was to assured the face validity of translated questionnaire.
The validity testing
According to Burns and Grover (2005), the valid of instrument may be valid
in situation, but not valid in another. Thus, the validity of instrument should be
reexamined. The three experts, including 1 nursing management educators, 1 nursing
educator and 1 medical psychologist were selected for checked validity. They are
experts in research and English. A content validity index (CVI) was calculated by
S-CVI/UA (Universal agreement) approach method (Polit & Beck, 2008). The result
of CVI reported to be 1.00 in this study.
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The reliability testing
The version of the Vietnamese instruments were tested for internal
consistency reliability before conducting the actual study. Internal consistency used
the Cronbach’s alpha coefficients to determine the reliability of each part of the
questionnaire. The primary reliability testing was carried out thirty staff nurses
working in Bac Kan Provincial General Hospital in September, 2010 where had
similar characteristics to the Thai Nguyen Provincial General Hospital such as
structure, organizational system but only different about total number of staff nurses,
total number of beds (Vietnam Association Young Physician [VAYP], 2009).
These thirty staff nurses were selected from the three clinical units including
medical unit, surgical unit, and intensive care unit. These thirty staff nurses who had
similar characteristic to the subject and not included in the main study used to test the
reliability. In this study, the Cronbach’s alpha obtained for ENSS, RCAS, JSS were
0.94, 0.80, 0.80.
Data collection procedures
The data collection was carried out from September through October, 2010.
The procedure was as follows:
1. The thesis proposal was granted ethical approval from Burapha
Institutional Review Broad (Burapha-IRB) by submitting research approval
document. After obtained the permission to collect the data. A separate letter from the
Dean of Faculty of Nursing, Burapha University (Appendix 2) was sent to the
Director of Health Department of Thai Nguyen Province.
2. The researcher was obtained the permission from Director of Provincial
Department of Health in Thai Nguyen province for all the three hospital authorities to
collect the data by submitting approval document and the introducing letter to conduct
the research.
3. The researcher obtained the permissions from director of hospitals as
well as nursing administrator to collect the data.
4. The researcher obtained the lists of the potential respondents from the
Department of Personnel and Organization of the three hospitals. And then, the
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researcher selected participants by using simple random sampling method from the
lists.
5. The researcher met the head nurses in the three units in each of hospitals
for an orientation to the study, informed the objectives of the study, and required them
about the supports to establish the meeting with participants.
6. The researcher contacted with the participants in one hour at the
conference room after the annual meeting. And then, explains the objectives of study,
and invites them to participate in the study, ask for their voluntary. Then give consent
form to each subject who was willing to participate. The cover letter explains the
nature of the study, invitations for participation in the study, and provided assurances
of the anonymous, voluntary, and confidential nature of the responses, method for
insuring confidentiality and assurance that participation is voluntary.
8. After receiving the written consent forms, the questionnaires were handdelivered direct to the participants by the researcher. The participants were asked to
mark the section immediately by using paper and pencil self-rating questionnaires,
and return them direct to the researcher. The researcher waited for complete, and
collected the responses.
9. The researcher reviewed all the data, and asked the subjects do
completely their questionnaires, which give incomplete answers. Then the researcher
prepares the data for analysis.
10. The researcher codes the questionnaires.
11. Entering data into the computer.
Data analysis
The data was coded and was entered into statistical program. Data analyzed
using descriptive and inferential statistics as determined by the level of measurement.
An alpha level of 0.5 was considered as statistical significance.
Descriptive statistical tool including means ( X ), percentage (%), standard
deviations (SD), and frequency distribution (n) were used to describe the demographic
data of the sample; levels of the job stress score and eight subscales scores; levels of
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the total job satisfaction score and nine subscales scores; levels of role stress and two
subscales scores.
The Pearson product-moment correlation coefficients (r) were calculated to
determine the relationships between job stress, role conflict, role ambiguity and job
satisfaction. The correlation coefficient ranges from +1.00 through 0.00 to -1.00. If
the r-value is +1.00, there is a perfect positive linear relationship. If the r-value is 1.00, there is perfect negative linear relationship or a perfect reverse relationship. If
the r-value is 0.00, there is no correlation.
Table 10 The correlation values and magnitude of correlations (Cohen, 1988)
Correlation
Positive
Negative
Small
0.10 to .29
- 0.29 to -.10
Moderate
0.30 to .49
-0.49 to -.30
High
0.50 to 1.00
-1.00 to -.50
If the r-value equals 0.10 to 0.29 or -0.29 to -0.10, correlation was
interpreted as small. If the r-values is 0.30 to 0.49 or -0.49 to -0.30, there was a
moderate correlation and if the r-values equals 0.50 to 1.00 or -1.00 to -0.50, there
was a high correlation between the two given variables. An alpha (α) level of ≤ .05
was deemed statistically significant for all inferential test utilized: Pearson’s productmoment correlations and Spearman rank-order correlations.
Multiple Regression Analysis: In response to the objective, to examine
which factors among job stress, role conflict and role ambiguity are able to predict job
satisfaction. The Stepwise Multiple Regression Analysis is used to predict the
relationships between independent variables (job stress, role conflict, role ambiguity)
and one dependent variable (job satisfaction). This procedure can find which variable
has most influence on the variance of dependent variable. The analysis result is
presented with an equation which consists of independent variables that have the
significant effect on with the dependent variable. This is the best equation for value
estimation of dependent variable. The assumptions of regression analysis were tested
including normality of dependent and independent variables, multicolinearity,
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linearity, autocorrelation and homocedasticity. The basic assumptions for data
analysis consisted of:
1. Normal distribution
Using a histogram of standardized residuals, assessed relationships are linear
and the dependent variable is normally distributed for each value of the independent
variable. The distribution of the residuals should be approximately normal (Munro,
2001). Furthermore, the researcher had tested the normal distribution of standardized
residuals by using Kolmogrove-Sminov test, the result of Kolmogrove-Sminov test
has to be non-significance. These indicated the standardized residuals were normal
distribution.
In addition, the researcher also used Fisher skewness coefficient (Skew/S.E)
to test the normal distribution of dependent and independent variables. When the
result of Fisher skewness coefficient lies between -1.96 and 1.96 meaning that is
significant and the normal distributions were found by statistic.
2. Multicollinearity
The Pearson’s product-moment correlation coefficient was used to test the
relationships between independent variables. This assumption obtains when the
correlation among the independent variables should not multicollinearity meaning that
the correlation coefficient among the independent variables should not higher than
0.80 (Munro, 2001). In addition, tolerance of a variable is used as a measure of
collinearity, which variables with high tolerances have small variance inflation
factors, and vice versa (Munro, 2001).
3. Homoscedasticity
Scatter plot was selected to test the homoscedasticity. The residuals can be
plotted against the predicted values and against the independent variables. When
standardized predicted values are plotted against observed values, the data would
form a straight line from the lower-left corner to upper right corner, if the model fitted
the data exactly. In general, they cluster fairly close around the prediction line
(Weisberg, 1980).
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4. Linearity
When the residuals are from a normal distribution, the plotted values fall
close to the line in the normal probability plot. Thus, the probability was selected to
check this assumption.
5. Autocorrelation
The Durbin-Wastson was selected to examine the autocorrelation of
residual. If Durbin-Wastson value lies between 1.5 and 2.5, it means that the residual
was no autocorrelation.
Ethical consideration
Before collecting the data, approvals for conducting the study were obtained
from Burapha University, Thailand and Provincial Department of Health of Thai
Nguyen Province, Vietnam. Permissions conducting the study were obtained of the
three hospitals. Following the completion of these formalities, letter of introduction to
research and the requirements of participation as well as the questionnaires were
handed out to nurses. To ensure the anonymity and confidentiality of responses, no
names were attached to survey; instead their responses were coded so that they would
not be identified.
The participants were informed that participations in the study to be purely
voluntary and that no remuneration would be given. The participants were told that
information they provide would be kept confidential and would only used for the
purposes intended, and was subject to all the legal requirements regarding data
collection. The participants were also assured that only the overall results would be
shared with ministry, health center and the nursing administrators for the purpose of
designing the needed managerial interventions.
During to data collection, the subjects want to refuse or withdraw from the
study, the researcher will respect their decision, and to assure anonymity and
confidentiality, and no penalty for withdrawal or termination from the study.