Download Which quality of life instruments are preferred by cancer patients in

Support Care Cancer (2014) 22:3135–3141
DOI 10.1007/s00520-014-2287-z
ORIGINAL ARTICLE
Which quality of life instruments are preferred by cancer patients
in Japan? Comparison of the European Organization
for Research and Treatment of Cancer Quality of Life
Questionnaire-C30 and the Functional Assessment
of Cancer Therapy-General
Kazuki Sato & Megumi Shimizu & Mitsunori Miyashita
Received: 27 December 2013 / Accepted: 12 May 2014 / Published online: 28 May 2014
# Springer-Verlag Berlin Heidelberg 2014
Abstract
Purpose We compared two health-related quality of life
(HRQOL) instruments used for cancer patients [the European
Organization for Research and Treatment of Cancer Quality of
Life Questionnaire-C30 (EORTC QLQ-C30) and the Functional Assessment of Cancer Therapy-General (FACT-G)] to
identify which instrument cancer patients most preferred.
Methods Adult cancer patients who had received cancer treatments within the previous 2 years (n=395) completed both
surveys; participants assessed the importance, necessity, and
appropriateness of each as an indicator of their quality of life.
Results The patients significantly preferred the FACT-G over
the EORTC QLQ-C30 as a more important (effect size (ES)=
0.37, P<0.001), necessary (ES=0.18, P<0.001), and appropriate questionnaire (ES=0.14, P=0.005). The subgroups of
patients with good performance status, and those who reported
low levels of work disruption, significantly preferred the
FACT-G more than the other. The corresponding correlation
coefficients were the following: physical functioning and
well-being subscale, r=0.65; emotional functioning and
well-being subscale, r=0.60; social functioning and social/
family well-being subscale, r=0.00; and role functioning
and functional well-being subscale, r=0.41.
Conclusions We recommend using the FACT-G if the performance status of the subject is good, e.g., in outpatient or
cancer survivor surveys, based on the observed patient preferences. When performance status is not good, an instrument
should be chosen after considering the differences between
K. Sato (*) : M. Shimizu : M. Miyashita
Department of Palliative Nursing, Health Sciences, Tohoku
University Graduate School of Medicine, 2-1 Seiryo-machi,
Aoba-ku, Sendai, Miyagi 980-8575, Japan
e-mail: [email protected]
their scale structures and social domains and based on the
availability of disease-specific modules.
Keywords Quality of life . Questionnaires . Neoplasm .
Patient preference . Japan . Palliative care
Introduction
Health-related quality of life (HRQOL) is now recognized as a
key outcome in cancer patients, in both the research and
clinical settings. HRQOL is a multidimensional construct
including physical, psychological, social, and spiritual wellbeing [1]. Of all the cancer-specific HRQOL instruments
available, the most commonly used in clinical research are
the European Organization for Research and Treatment of
Cancer Quality of Life Questionnaire-C30 (EORTC QLQC30) and the Functional Assessment of Cancer TherapyGeneral (FACT-G). The characteristics of the two questionnaires are shown in Table 1.
The EORTC QLQ-C30 incorporates nine multi-item
scales: five functional scales (physical, role, cognitive, emotional, and social), three symptom scales (fatigue, pain, and
nausea and vomiting), and a global health and quality of life
scale [1]. It has been translated and validated into 81 languages and has been used in more than 3,000 studies worldwide [5]. The survey can be supplemented with diseasespecific modules, and there is also a shortened version, which
is suitable for research in palliative care, that consists of 15
items [8].
The FACT-G is a 27-item compilation of general questions,
which are divided into four primary HRQOL domains: physical well-being, social/family well-being, emotional well-
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Table 1 Characteristics of the EORTC QLQ-C30 and FACT-G
Number of items
Response scale
Recall period
Scaling
EORTC QLQ-C30
FACT-G
30
Likert scale (4 or 7 points)
Past week
5 functional scales
• Physical functioning (e.g., Do you have any trouble doing
strenuous activities, like carrying a heavy shopping bag
or a suitcase?—5 items)
• Role functioning (e.g., Were you limited in doing either
your work or other daily activities?—2 items)
• Emotional functioning (e.g., Did you feel tense?—4 items)
• Cognitive functioning (e.g., Have you had difficulty in
concentrating on things, like reading a newspaper or
watching television?—2 items)
• Social functioning (e.g., Has your physical condition or
medical treatment interfered with your family life?
—2 items)
Symptom scale
• Fatigue (3 items)
• Pain (2 items)
• Nausea and vomiting (2 items)
• Six single-item symptoms: dyspnea, sleep disturbance, appetite
loss, constipation, diarrhea, and financial difficulties
Overall global health status
27
Likert scale (5 points)
Past 7 days
4 well-being subscales
• Physical well-being (e.g., I have a lack of energy—7 items)
being, and functional well-being [2]. This has been validated
not only for cancer but also in a range of chronic diseases. It
has been translated and validated into more than 50 languages;
there are more than 50 different scales and symptom indexes
[6]. There is a shortened version of a rapid symptom/concern
scale that consists of seven items [17] and another version for
the assessment of QOL in palliative care patients, which
consists of 14 items [18].
There is uncertainty about which HRQOL instrument
should be recommended for use. A systematic review reported
comparisons between the EORTC QLQ-C30 and the FACT-G
[12]. The author concluded that while the psychometric evidence is inconclusive, there are important differences between
the two instruments in terms of their structure, social domains,
and tone. The social HRQOL is conceptualized and measured
differently: the EORTC QLQ-C30 assesses impacts on social
activities and family lives, whereas the FACT-G focuses on
social support and relationships. With respect to scale structure, the EORTC QLQ-C30 provides 15 scores of specific
interest compared with the FACT-G’s five scores. The psychometric data are not sufficient to recommend one measure
over the other. In terms of tone, the EORTC QLQ-C30 functional questions focused on trouble or interference in activities, whereas the FACT-G functional questions encouraged
respondents to reflect on their thoughts and feelings. The
HRQOL instrument should have content validity that is important for cancer patients. However, the patients’ preferences
for these different instruments are unknown because previous
studies had serious limitations in terms of generalizing patient
• Social/family well-being (e.g., I feel close to my friends—
7 items)
• Emotional well-being (e.g., I feel sad—6 items)
• Functional well-being (e.g., I am able to work (include work
at home)—7 items)
Overall FACT-G score (total of all items)
preferences because they had small sample sizes and were
biased in the types of primary cancer sites they studied.
The primary aim of this cross-sectional, observational
study of cancer patients was to compare the EORTC
QLQ-C30 and FACT-G to identify which instrument
cancer patients preferred most, in terms of importance,
necessity, and appropriateness of each as an indicator of
their quality of life.
Methods
Study design and participants
We conducted a cross-sectional, observational online survey
in 2011. The Ethics Committee of the Tohoku University
Graduate School of Medicine approved this study (2010-388).
A convenience sample of 400 adult cancer outpatients, who
had received cancer treatments (surgery, chemotherapy, or
radiation) within the preceding 2 years and who had visited
a hospital clinic within the last 6 months, was obtained from
an internet panel of a market research company (INTAGE
Inc., Tokyo, Japan). Hematological cancer patients were excluded. To prevent bias arising from the type of cancer site, we
requested an even sample of six major cancer types: lung,
gastric, colon, hepatobiliary, breast, and others, up to a total of
400 patients. About 4,000 cancer patients were registered in
the internet panel.
Support Care Cancer (2014) 22:3135–3141
Measures
Data were collected on (1) the EORTC QLQ-C30 and FACTG, (2) preferences about EORTC QLQ-C30 and FACT-G, and
(3) details relating to the cancer patients’ background.
The EORTC QLQ-C30 (version 3.0, Japanese version) and
the FACT-G (version 4.0, Japanese version) were used. The
EORTC QLQ-C30 consisted of 30 items, including five functional subscales (physical, role, emotional, cognitive, and
social), a global health status, and nine symptom subscales;
scores range from 0 to 100. Higher scores indicated better
QOL for the functional subscales and global QOL, whereas a
high score indicated a worse QOL for the symptom scales [1,
11]. The FACT-G consisted of 27 items, including four wellbeing subscales, as previously described, with the scores
ranging from 0 to 100; a total score was calculated using all
of the items. Higher scores indicate a better QOL [2, 7].
Preferences relating to the EORTC QLQ-C30 and FACT-G
were measured by importance, necessity, and the appropriateness of each instrument as an indicator of their quality of life.
These questions were based on the previous research [15]. We
asked whether the items within each instrument included the
following: (1) “important matters for you,” (2) “the matters
that you would like to be cared by health care providers”, and
(3) “appropriate matters to evaluate the quality of life for
cancer patients.” The results were recorded separately for the
EORTC QLQ-C30 and FACT-G using a 4-point Likert scale
from “1. I do not think so at all” to “4. I strongly think so.”
The patient characteristics included sex, age, marital status,
employment disruption caused by the cancer, the primary
cancer site, length of time since cancer diagnosis, time since
last cancer treatment, and their Eastern Cooperative Oncology
Group (ECOG) performance status.
Analysis
First, we reported descriptive statistics, internal consistency,
and known-group validity; then, we calculated Pearson correlation coefficients to assess the relationship between the
EORTC QLQ-C30 and FACT-G subscales. Internal consistency was evaluated using Cronbach’s alpha coefficient.
Known-group validity was evaluated by comparing mean
scores between the two subgroups having high and low performance status using t test. We assumed that conceptually
corresponding relationships were the following: physical
functioning and well-being subscale, emotional functioning
and well-being subscale, social functioning and social/family
well-being subscale, and role functioning and functional wellbeing subscale. Second, the evaluations of importance, necessity, and appropriateness of both instruments were compared
using Student’s t test. We calculated Hedges’ G to estimate
effect sizes (ES) [9]. For interpretation, we deemed effect sizes
of 0.2 as small, 0.5 as moderate, and 0.8 as large [4]. In
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addition, we compared the evaluations between different patients’ backgrounds. The significance of differences between
the different subgroups was assessed by interaction terms. We
also calculated effect sizes in the significant subgroups. We
examined the results of subgroup analysis of the importance,
necessity, and appropriateness of both instruments in cases of
significant interaction effects. P values of less than 0.05 were
considered to be statistically significant. All tests were twotailed. Statistical analyses were performed with SAS version
9.3 for Windows (SAS Institute, Cary, NC).
Results
There were 400 cancer patients who responded to the questionnaires; 395 (99 %) were analyzed because five were
excluded due to missing data. All patients had received cancer
treatments within the preceding 2 years and visited a hospital
clinic within the last 6 months.
The cancer patients’ backgrounds are described in Table 2.
Among these patients, 52 % were male and the mean age of all
participants was 54 years. The ECOG performance status was
63 % in 0 and 31 % in 1; 63 % of patients had employment
although 47 % of this group were experiencing disruptions in
their work because of their cancer. Forty-seven percent of the
patients had been diagnosed within 2 years, and 29 % had
received cancer treatments within the preceding 6 months.
Table 3 lists the scores, internal consistency, and knowngroup validity of the EORTC QLQ-C30 and FACT-G surveys.
For the EORTC QLQ-C30, the mean of overall global health
status was 66; the functional and symptom subscales ranged
from 80 to 90 and 9 to 29, respectively. For the FACT-G, the
mean of the total scores was 58 and the well-being subscales
ranged from 48 to 78. Cronbach’s alpha ranged from 0.73 to
0.94 and from 0.72 to 0.91 in the EORTC QLQ-C30 and
FACT-G subscales, respectively. All EORTC QLQ-C30 and
FACT-G subscales but one subscale were significantly different between high and low performance status subgroups.
Social/family well-being in the FACT-G was not significantly
different (P=0.689).
Table 4 lists the correlation between the subscales of the
two instruments. The conceptually corresponding correlation
coefficients were as follows: physical functioning and wellbeing subscale, r=0.65; emotional functioning and well-being
subscale, r=0.60; social functioning and social/family wellbeing subscale, r=0.00; and role functioning and functional
well-being subscale, r=0.41.
Table 5 lists the importance, necessity, and appropriateness
of the EORTC QLQ-C30 and the FACT-G as an indicator of
their quality of life. For all the subjects, they significantly
preferred the FACT-G more than the EORTC QLQ-C30, with
the former being: more important (ES=0.37, P<0.001),
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Table 2 Cancer patient characteristics
Sex
Male
Female
Age, years
Less than 45
45 to 54
55 to 64
65 or more
Mean±SD
Marital status
Married
Not married
ECOG performance status
0
1
2
3
Number
Percent
205
190
52 %
48 %
74
142
115
82
54
19 %
36 %
29 %
21 %
±11
318
67
81 %
17 %
250
124
15
6
63 %
31 %
4%
2%
4
0
Work status
Full-time/part-time
249
None
146
Current disruption of work because of cancer
Definitely
30
To some extent
153
Not so much
118
Not at all
94
Primary cancer site
Lung
46
Gastric and esophageal
89
Colon and rectum
53
Hepatobiliary and pancreatic
31
Breast
89
Others
87
Length of time since cancer diagnosis
5 months or less
20
6 to 11 months
18
1 to 2 years
145
2 to 5 years
186
5 years or more
26
Length of time since the last cancer treatment
Within 3 months
86
3 to 6 months
26
6 to 12 month
50
12 to 24 month
233
0%
63 %
37 %
8%
39 %
30 %
24 %
12 %
23 %
13 %
8%
23 %
22 %
5%
5%
37 %
47 %
7%
22 %
7%
13 %
59 %
SD standard deviation, ECOG Eastern Cooperative Oncology Group
necessary (ES=0.18, P<0.001), and appropriate (ES=0.14,
P=0.004).
The evaluation of importance and necessity was significantly different between both the ECOG performance statuses
(P=0.001 and P=0.048) and the degree of employment disturbance (P=0.009 and P=0.001). Appropriateness was significantly different between work statuses (P=0.002). Significant subgroup analyses of importance, necessity, and appropriateness are shown in Table 5. The ES of the difference of
importance between the EORTC QLQ-C30 and the FACT-G
tools were the following: 0.52 and 0.15 in performance status,
0 and 1 or more, and 0.27 and 0.47 for the patients with or
without disturbances at work. Similarly, the ES of the differences of necessity were 0.25 and 0.05 in performance status
and 0.00 and 0.33 for disturbances at work. The ES of the
differences of appropriateness were 0.25 and 0.06 for with or
without work.
Discussion
Overall, the patients significantly preferred the FACT-G over
the EORTC QLQ-C30 in terms of importance, necessity, and
appropriateness as an indicator of their quality of life. Both are
reliable and valid for use in oncology, and to the extent that
one wishes to use an instrument preferred by patients in terms
of importance or appropriateness, the FACT-G edges out the
EORTC QLQ-C30 by a small but significant margin. However, we are unable to recommend one of the instruments over
another in general because the patient preference for the
instrument is only one criterion to use. Conversely, we do
recommend using the FACT-G if the performance status of
subjects is good, e.g., in an outpatient or cancer survivor
survey, because our study showed moderate to small effect
size.
The rationale for this recommendation is that cancer patients with a good performance status generally experience
less distressing symptoms. The general health trajectory of
cancer patients is for their performance status to remain high
early in their final year, which then decreases markedly during
the final 3 months [13, 14]; pain and other symptoms such as
tiredness, poor appetite, shortness of breath, and drowsiness
are common complaints 6 months prior to death, and these
generally worsen over time [14, 16]. In this study, 7 medians
out of 9 symptom scales in the EORTC QLQ-C30 were zero.
As a consequence, the FACT-G may have an advantage in
terms of patient preference for many cancer patients who are
not in the terminal phase and with good performance status
because the EORTC QLQ-C30 includes a range of symptom
items that are not applicable for many cancer outpatients and
not assessed by the FACT-G [12].
Another issue to consider when choosing a HRQOL instrument for cancer patients relates to differences in the measurement concept. Our results relating to the correlation between corresponding subscales are similar to those of previous
Support Care Cancer (2014) 22:3135–3141
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Table 3 Scores, internal consistency, and known-group validity of the EORTC QLQ-C30 and FACT-G
EORTC QLQ-C30
Overall global health status
Physical functioning
Role functioning
Emotional functioning
Cognitive functioning
Social functioning
Fatigue
Nausea and vomiting
Pain
Dyspnea
Sleep disturbance
Appetite loss
Constipation
Diarrhea
Financial difficulties
FACT-G
Total score
Physical well-being
Social/family well-being
Emotional well-being
Functional well-being
Mean±SD
Median [IQR]
Alpha
Mean±SD
(PS=0)
Mean±SD (PS>0)
P value
66±23
90±15
86±22
67 [50, 83]
93 [87, 100]
100 [67, 100]
0.94
0.83
0.91
74±20
96±8
95±12
53±23
79±18
70±26
<0.001
<0.001
<0.001
80±22
81±22
82±25
29±24
9±20
13±22
17±23
16±26
12±24
19±28
18±26
26±30
83 [67, 100]
83 [67, 100]
100 [67, 100]
22 [11, 44]
0 [0, 0]
0 [0, 17]
0 [0, 33]
0 [0, 33]
0 [0, 0]
0 [0, 33]
0 [0, 33]
33 [0, 33]
0.88
0.73
0.84
0.87
0.88
0.88
–
–
–
–
–
–
85±18
88±17
89±19
18±17
4±13
5±12
9±16
7±18
5±16
14±24
12±22
18±26
70±25
70±25
68±28
46±25
18±27
26±27
30±27
30±30
23±31
27±32
28±29
41±31
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
<0.001
56±6
78±19
48±15
64±16
61±18
56 [52, 59]
82 [66, 100]
49 [43, 55]
64 [53, 72]
61 [50, 69]
0.75
0.91
0.85
0.72
0.90
58±5
87±14
49±16
68±14
66±17
52±6
62±17
48±14
55±15
52±14
<0.001
<0.001
0.689
<0.001
<0.001
The scores range from 0 to 100. Higher scores indicated better QOL for the functional subscales and global QOL in the EORTC QLQ-C30 and the total
score and all well-being subscales in the FACT-G, whereas a high score indicated a worse QOL for the symptom scales in the EORTC QLQ-C30
IQR interquartile range, Alpha Cronbach’s alpha coefficient, PS Eastern Cooperative Oncology Group performance status
Table 4 Pearson correlations between the subscales of the
EORTC QLQ-C30 and FACT-G
FACT-G
Total score
Physical
well-being
Social/family
well-being
Emotional
well-being
Functional
well-being
0.54*
0.41*
0.45*
0.46*
0.46*
0.41*
−0.49*
−0.32*
−0.45*
−0.37*
−0.50*
0.52*
0.65*
0.67*
0.56*
0.57*
0.63*
−0.71*
−0.53*
−0.61*
−0.55*
−0.56*
0.18*
0.00
0.03
0.04
0.12*
0.00
−0.01
0.00
−0.06
0.03
−0.10
0.43*
0.31*
0.38*
0.60*
0.41*
0.40*
−0.41*
−0.27*
−0.40*
−0.27*
−0.41*
0.57*
0.44*
0.41*
0.41*
0.37*
0.36*
−0.47*
−0.28*
−0.41*
−0.31*
−0.46*
Appetite loss
Constipation
Diarrhea
−0.42*
−0.26*
−0.31*
−0.56*
−0.31*
−0.46*
−0.03
−0.05
−0.04
−0.33*
−0.26*
−0.27*
−0.36*
−0.22*
−0.22*
Financial difficulties
−0.40*
−0.54*
−0.03
−0.40*
−0.35*
EORTC QLQ-C30
Overall global health status
Physical functioning
Role functioning
Emotional functioning
Cognitive functioning
Social functioning
Fatigue
Nausea and vomiting
Pain
Dyspnea
Sleep disturbance
*P<0.05 (means significant
correlation)
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Table 5 Importance, necessity,
and appropriateness of the
EORTC QLQ-C30 and FACT-G
as indicators of the patients’
quality of life
EORTC QLQ-C30
FACT-G
P value
Mean±SD
Mean±SD
Effect size
Importance
2.5±0.7
Necessity
2.5±0.7
Appropriateness
2.7±0.6
(Subgroup analysis)
ECOG PS was in 0 (n=250)
–
Importance
2.4±0.7
Necessity
2.3±0.7
Appropriateness
–
ECOG PS was in 1, 2, and 3 (n=145)
Importance
2.8±0.7
Necessity
2.7±0.7
Appropriateness
–
Work status was in full-time/part-time (n=249)
Importance
–
Necessity
–
Appropriateness
2.6±0.6
Work status was in none (n=146)
Importance
–
Necessity
–
2.8±0.6
2.6±0.6
2.8±0.6
0.37
0.18
0.14
<0.001
<0.001
0.004
–
2.7±0.6
2.5±0.7
–
–
0.52
0.25
–
–
<0.001
<0.001
–
2.9±0.6
2.7±0.6
–
0.15
0.05
–
0.009
0.323
–
–
–
2.8±0.6
–
–
0.25
–
–
<0.001
–
–
–
–
–
–
Appropriateness
2.8±0.6
Work is currently being disturbed by cancer (n=183)
Importance
2.7±0.7
Necessity
2.6±0.6
Appropriateness
–
Work is not currently being disturbed by cancer (n=213)
Importance
2.4±0.7
Necessity
2.3±0.7
Appropriateness
–
2.8±0.5
0.06
0.282
2.8±0.6
2.6±0.6
–
0.27
0.00
–
<0.001
1.000
–
2.7±0.6
2.5±0.7
–
0.47
0.33
–
<0.001
<0.001
–
All subject
The results of subgroup analysis
are shown when the difference
between the different subgroups
was significant, as assessed by the
interaction term
SD standard deviation, ECOG PS
Eastern Cooperative Oncology
Group performance status
studies [12]. Low correlations between the social functioning
in the EORTC QLQ-C30 and social well-being in the FACT-G
reflect differences in their content; items in the former assess
impacts on social activities and family life compared with
those in the latter, which focus on social supports and relationships. The concept of the social functioning in the EORTC
QLQ-C30 would rather be similar as the physical well-being
subscale in the FACT-G although the social well-being in the
FACT-G did not correlate with any other subscales. If the
social domain is of special interest to evaluate, the HRQOL
instrument should be chosen by the interest to either “social
activities and family life” or “social supports and
relationships.”
The EORTC QLQ-C30 has another advantage of providing
brief scales about cognitive functioning, financial impacts, as
well as a range of symptoms that are either not assessed by the
FACT-G or are embedded within its well-being scales. On the
other hand, the FACT-G is easy to interpret because it uses a
total score from all 27 items and a simple four-domain construct. In addition, the feasibility of self-reported questionnaires can become a major issue during the terminal phase
because end-of-life patients are often too ill to report their
health status. Both instruments have short versions that can be
used in palliative settings [8, 18]. Both also have the advantage of providing evidence-based effect sizes to decide on a
sample size and interpret clinical importance [3, 10]. It is also
advisable to consider issues relating to the availability of
disease-specific modules for both the EORTC QLQ-C30 and
FACT-G before selection.
Our study has several limitations. First, the online survey
may have caused selection bias by selecting a relatively
healthy and younger sample in outpatient settings; the preferences of seriously ill patients are still unknown. Second, using
a patient survey limited the collection of detailed information
Support Care Cancer (2014) 22:3135–3141
about the patients’ disease condition, e.g., their cancer stage.
The third limitation may have been our recommendation to
choose a general questionnaire for cancer patients and not
consider the use of disease-specific modules. The patients’
preferences for HRQOL questionnaire may differ between
general questionnaires and disease-specific modules.
Conclusion
This study provides important information for researchers and
clinicians about the use of general HRQOL instruments for
cancer patients. We do recommend using the FACT-G if the
performance status of the subject is good, e.g., in an outpatient
survey or cancer survivor survey, based on the patient preferences observed in this study. When performance statuses are not
good, the instrument should be chosen after considering the
differences between their scale structures and social domains
and based on the availability of disease-specific modules if
needed.
Acknowledgments This study was supported by a Health and Labour
Sciences Research Grant for the Clinical Oncology Research Project.
Conflict of interest There is no conflict of interest to declare.
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