Rheumatology 2006;45:1298–1302
Advance Access publication 4 June 2006
doi:10.1093/rheumatology/kel189
Impact of pain in health related quality of life of patients
with systemic sclerosis
C. Georges, O. Chassany1, C. Toledano, L. Mouthon2, K. Tiev3, O. Meyer4, D. Ilie,
J. Rambeloarisoa, Z. Marjanovic, J. Cabane3, D. Sereni, J. Pouchot5 and D. Farge
Objectives. Systemic sclerosis (SSc) has an heterogenous clinical pattern, with variable organ involvement and degrees of
severity. Like in other rheumatic diseases, the self-questionnaires have been used to evaluate SSc globally. The aim of the study
is as to evaluate the quality of life (QoL) in patients with either diffuse or limited SSc, and to examine the impact of pain on the
QoL scores.
Methods. Patients with SSc, eitheir diffuse or limited SSc, were included in a cross-sectional study. The QoL was evaluated with
the short-form 36 (SF-36) and the functional repercussion with the SSc-modified Health Assessment Questionnaire (S-HAQ).
Results. A total of 89 patients (67 with diffuse and 22 with limited SSc) were included. The SF-36 score values were lower in
SSc patients than those reported in the general population. The physical component scores (PCS) of the SF-36 was significantly
worse in diffuse compared with limited SSc (P < 0.05). The PCS was significantly negatively related to the number of clinical
manifestations (ANOVA, P < 0.0001). The mental component score (MCS) was not influenced by the type of SSc or the
number of clinical manifestations presented by the patient. The QoL of SSc patients was highly correlated with pain (R ¼ 0.69)
and disability (R ¼ 0.70). Interestingly, the QoL of SSc patients was only slightly correlated with cutaneous (R ¼ 0.42)
and pulmonary involvement (R ¼ 0.57).
Conclusion. The QoL of patients with SSc is strongly influenced by the type of SSc, the burden of clinical manifestations,
the functional disability and by the pain, whatever its cause. The treatment of pain should be considered as priority to improve
the QoL of SSc patients.
KEY
WORDS:
Systemic sclerosis, Pain, Quality of life.
Introduction
Systemic sclerosis (SSc) is a rare debilitating disease with a
heterogenous clinical pattern, variable organ involvements and
degrees of severity. This disabling disease may alter the health
related quality of life (QoL), depending on the extent of skin,
heart, lung, kidney or digestive tract involvement. Painful
symptoms of various causes [Raynaud’s phenomenon (RP),
digital ulcerations, oesophagitis, arthritis, etc.] may contribute to
alter the QoL in this disease.
Like in other rheumatic or non-rheumatic diseases, it has been
recently reported that the short-form 36 (SF-36) is an accurate
tool to evaluate QoL in SSc [1] and that the QoL evaluated with
this score was altered in SSc and correlated with the severity of
the disease [1–3].
Therefore, the aims of this prospective multicentre observational study were to examine the impact of SSc on QoL and to
determine the impact of pain in the QoL of SSc patients with
either a limited or a diffuse form of SSc.
Patients and methods
Patients
We included 89 SSc consecutive patients, who were either
hospitalized or seen at the outpatient clinics in four hospitals
from March 2001 to September 2004. To be included, every patient
had to fulfil the American College of Rheumatology (ACR)
criteria for SSc or the criteria for limited SSc proposed by LeRoy
and Medsger [4] and possess a good knowledge of French
language, with sufficient capacity for abstract thought to understand the concept of visual analogue scale (VAS).
The SSc patients were defined as having diffuse SSc if
they had a proximal cutaneous skin sclerosis and at least one
type of visceral involvement. Otherwise, they were classified as
limited.
Methods
We performed a prospective cross-sectional study. After a brief
explanation of the aims of the study, each SSc patient was asked
to complete two self-administered questionnaires, the French
versions of the SSc health assessment questionnaire (HAQ) [5] and
the SF-36 [6]. At the same time, they underwent a complete
clinical examination by their referring physician. All patients gave
written, informed consent.
For each patient included in the study, the following data were
recorded: age, gender, type of SSc (diffuse or limited), duration
of the disease and coexisting disease. Clinical and paraclinical
parameters were recorded for each SSc patient as part of the
information gathered during their routine follow-up.
Internal Medicine and 1Clinical Research Delegation, Saint Louis Hospital, 2Internal Medicine, Cochin Hospital, 3Internal Medicine, Saint Antoine Hospital,
4
Rheumatology, Bichat Hospital and 5Internal Medicine, Georges Pompidou Hospital, Paris, France.
Received 7 February 2006; revised version accepted 25 April 2006.
Correspondence to: Dr C. Georges, Internal Medicine Department, Saint Louis Hospital, Service de Médecine Interne, Hôpital Saint Louis, 1 avenue
Claude Vellefaux, 75010 Paris, France. E-mail: [email protected]
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ß The Author 2006. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: [email protected]
Impact of pain in health scleroderma quality of life
The medical outcome study (MOS)
short-form 36 (SF-36)
We measured the health-related quality of life using the ‘Medical
Outcome Study (MOS) SF-36 Health Survey’. SF-36 is a 36-item
self-questionnaire that evaluates the QoL within eight areas of
general health: physical function (PF), role physical (RP), bodily
pain (BP), general health (GH), vitality (VT), social function (SF),
role emotional (RE) and mental health (MH).
Scores were calculated for each of these different aspects of health
in the range of 0–100, the higher values reflecting a better QoL.
The 36 items leading to eight domain scores may also be
presented in two global scores: the physical component summary
score (PCS) and the mental component summary score (MCS).
The French version of SF-36 was translated and validated by
Leplege et al. [6] in 1998.
Scleroderma-modified HAQ (S-HAQ)
The functional repercussion of the SSc was evaluated by the
SSc-modified Health Assessment Questionnaire (S-HAQ) [7]. The
standard disability index of the Health Assessment Questionnaire
(HAQ-DI) was initially developed in rheumatoid arthritis. This
self-administered questionnaire contains 20 items (each scored
0–3), divided into eight domains of daily activity. The highest
scores in each domain were added and then divided by eight to
determine the HAQ-DI value, which is calculated as a continuous
variable, ranging from 0 (no disability) to 3 (severe disability).
A pain visual analogue scale (VAS) is also associated with the
HAQ-DI [8].
When constructing the S-HAQ, Steen and Medsger [7], added
five VASs to assess the functional impairment due to the following
SSc symptoms RP, digital lesions, gastrointestinal symptoms,
pulmonary symptoms and the overall severity of the disease, from
the patient’s perspective.
The S-HAQ was recently validated by our group in French
language [5].
Clinical and paraclinical data collection
For each patient included in the study, clinical examination and
functional evaluation were performed on the same day.
Paraclinical parameters were recorded within a 3-month interval
and compared with functional evaluation for each SSc patient
as part of the information gathered during routine follow-up.
The following data were recorded and analysed: age, gender, type
of SSc (diffuse or limited), duration of the disease (defined by
the time elapsed between the first symptoms of SSc and the
study entry) for all patients and coexisting disease.
Patient evaluation was made from Medsger’s proposed
criteria [9]:
(1) Skin evaluation using the Rodnan modified total skin score
[10], which was calculated as the total score from 17 body
areas (right and left fingers, hands, forearms, upper arms,
thighs, legs and feet plus face, anterior chest and abdomen),
each body area being assessed by palpation on a 0–3 scale
from uninvolved to severe thickening (range 0–51).
(2) Presence of
(a) RP crisis during the past week;
(b) digital lesions defined by pitting scars, digital tip
ulceration and/or digital gangrene on examination;
(c) musculoskeletal involvement defined by myalgia,
muscular weakness, peripheral arthralgia or arthritis
during the previous week; finger contracture on physical
examination was also noted;
(d) gastrointestinal symptoms defined by heartburn,
dysphagia, episodes of pseudo-occlusion or anal incontinence during the past week;
1299
(e) pulmonary involvement defined by carbon monoxide
diffusing capacity (DLCO) <60%, as measured on
pulmonary function tests;
(f) heart involvement was defined by the presence of any of
the following criteria after clinical examination, EKG
and cardiac ultrasound scan performed by an experienced
cardiologist: a conduction defect including second- and
third-degree auriculo-ventricular block, intraventricular
conduction disturbance, left axis deviation, atrial or
ventricular rhythm disturbance, pericarditis as defined
by the presence of moderate or severe pericardial effusion
>1 cm on cardiac echocardiography, left ventricular
ejection fraction below 50%;
(g) pulmonary arterial hypertension was defined by pulmonary arterial pressure >35 mmHg on cardiac ultrasound scan after ruling out any other non-scleroderma
related causes and
(h) renal involvement defined by serum creatinine
>1.3 mg/dl or bedside urinary proteins >1þ,
unexplained by any other cause but SSc.
Statistical analysis
Descriptive statistics were expressed as mean S.D., unless
otherwise stated. Student’s t-tests were used to compare the
continuous variables. A Chi-square test was used to analyse
categorical variables. Pearson correlation coefficients were used
to examine the degree of association among SF-36 scores and
other continuous variables. Comparison of SF-36 scores was
based on Mann–Whitney U-tests for ordinal data (i.e. absence
or presence of various organ involvement) and on Wilcoxon
tests for continuous data. Comparison of SF-36 scores
according to the number of organ involvements was performed
by ANOVA. A P-value below 0.05 was considered statistically
significant.
Results
A total of 89 patients (71 women) answered the SF-36 and were
clinically analysed at the same time [median age 51 yrs (19–77)],
67 with diffuse SSc and 22 with limited SSc. Table 1 shows the
characteristics of the patients. The disability (S-HAQ) and healthrelated QoL (SF-36) scores are reported in Table 2.
The highest correlations with the PCS of the SF-36 with the
VAS of the S-HAQ values were found for the general VAS
(R ¼ 0.71) and for the pain VAS (R ¼ 0.69) (Pearson correlation)
(Table 3). Figure 1 reports high correlation between the PCS of
the SF-36 and the pain VAS (R ¼ 0.69, P < 0.0001). In comparison, although not as high, there was a significant correlation
between the MCS of the SF-36 and the pain VAS (R ¼ 0.34,
P ¼ 0.001) (Fig. 1).
The PCS of the SF-36 highly correlated with the HAQ
(R ¼ 0.74, P < 0.0001), whereas the MCS correlated moderately
(R ¼ 0.35, P ¼ 0.001) (Pearson correlation) (Table 3).
The SF-36 scores were lower in patients with diffuse than with
limited SSc. The PCS of the SF-36 was statistically lower in diffuse
than in limited patients SSc, respectively, 34 11 vs 42 10
(P < 0.05) (Fig. 2). In the presence of either RP, digital lesions,
gastrointestinal, pulmonary, musculoskeletal or finger contracture, the PCS of the SF-36 was significantly lower. The MCS of
the SF-36 was significantly lower only in the presence of RP or
digital lesions (Table 4).
The higher was the number of SSc organ involvements, the
lower were the SF-36 scores. The PCS of the SF-36 was
significantly correlated with the number of clinical manifestations,
with scores ranging from 51 9 for the patients without any
clinical involvement to 22 8 with six clinical involvements
(ANOVA, P < 0.0001) (Fig. 3).
C. Georges et al.
1300
TABLE 1. Demographic data and characteristics of patients included in the
study (n ¼ 89). All the results were assessed for 89 patients except when
specified (*n ¼ 87)
70
Demographic and disease data
Gender
Age (yrs): median (range)
Type of SSc
Diffuse
Limited
Disease duration (yrs): median (range)
50
n ¼ 67 (75%)
n ¼ 22 (25%)
5 yrs (1–34)
Clinical involvement (n ¼ 89)
RP during the previous week
Digital lesions
Gastrointestinal symptoms during the previous week
Pulmonary symptoms
Musculoskeletal symptoms
Finger contracture
Pulmonary hypertension*
Heart involvement*
Kidney involvement
PCS
71 women
51 (19–77)
60
40
30
20
Percentage of
patients
67
54
49
53
59
31
15
9
6
10
0
−0.5
0
0.5
1
1.5
2
2.5
3
3.5
2
2.5
3
3.5
PAIN
70
60
TABLE 2. Functional disability measured with the S-HAQ and healthrelated QoL measured with the SF-36
Disability: S-HAQ (n ¼ 89)
HAQ-DI [0–3]
Pain VAS [0–3]
Raynaud’s phenomenon VAS [0–3]
Digital VAS [0–3]
Gastrointestinal VAS [0–3]
Pulmonary VAS [0–3]
Overall disease severity VAS [0–3]
Global SSc HAQ [0–3]
0.98 0.86
1.29 0.94
1.07 0.97
0.97 1.06
0.81 0.96
0.93 1.01
1.33 0.94
0.98 0.75
Health-related quality of life: SF-36 (n ¼ 89)
Physical function (PF)
Role limitation-physical (RP)
Bodily pain (BP)
General health (GH)
Vitality (VT)
Social function (SF)
Role limitation-emotional (RE)
50 31
40 42
47 28
41 22
39 22
58 28
46 44
HAQ-DI, Health assessment questionnaire - disability index; Global
SSc HAQ, global score of the S-HAQ. Global SSc HAQ ¼ (8 HAQ-DI
domains þ 5 VAS scores) divided by 13. HAQ-DI and global SSc HAQ
range from 0 (no impairment) to 3 (very severe limitation). The mean value
for MCS and PCS in the general population is 50 with an S.D. of 10.
A lower score indicates a poorer QoL. Results presented are mean S.D.
TABLE 3. Correlations between the PCS and the MCS of the SF-36 with
the seven VAS of the S-HAQ
HAQ-DI
Raynaud VAS
Digital VAS
Gastrointestinal VAS
Pulmonary VAS
General VAS
Pain VAS
PCS
MCS
0.74*
0.56*
0.55*
0.44*
0.53*
0.71*
0.69*
0.35***
0.47*
0.32***
0.36**
0.33***
0.41*
0.34**
*P < 0.0001, **P ¼ 0.001, ***P ¼ 0.002 (Pearson correlation).
The PCS of the SF-36 was slightly correlated with the Rodnan
modified total skin score (R ¼ 0.42), as well as with the DLCO
(R ¼ 0.41). In contrast, the MCS of the SF-36 was neither
correlated with the Rodnan modified total skin score nor
MCS
50
40
30
20
10
0
−0.5
0
0.5
1
1.5
PAIN
FIG. 1. Correlation between physical component summary score
(PCS) and mental component summary score (MCS) and visual
analogue pain scale, n ¼ 89. PCS: R ¼ 0.69 (P < 0.0001). MCS:
R ¼ 0.34 (P ¼ 0.001).
with the DLCO (R < 0.01). The score of DLCO obtained with
functional respiratory tests was highly correlated with the
pulmonary VAS of the S-HAQ (R ¼ 0.57).
There was no correlation between the age and the PCS
(R ¼ 0.04) or the MCS (R ¼ 0.07) of the SF-36. There was no
correlation between the disease duration and the scores of the
PCS or the MCS of the SF-36 either, except for the mental health
(MH) score which was slightly correlated with the disease
duration (R ¼ 0.26, P ¼ 0.01). The MH was the only dimension
of the SF-36, more altered in women (MH ¼ 53 19) than in men
(MH ¼ 64 24) (P < 0.05).
Discussion
The present multicenter prospective study, performed on a larger
cohort, of 89 SSc patients with both diffuse (n ¼ 67) and limited
(n ¼ 22) forms of the disease, than the previous similar studies in
SSc patients [2, 3, 11], confirmed that the QoL is diminished in
SSc. All the SF-36 subscale scores of SSc patients were lower than
those already reported in general population [6], as shown in
Table 5. Results were influenced by the type of SSc and both PCS
and MCS of the SF-36 were lower in diffuse than in limited SSc,
which could be related to the disease extension. Such a result was
not found by Del Rosso et al. [2], who observed a lower mental
score in 9 diffuse and 15 limited SSc. Differences in the total
number of patients and the respective ratio of localized and diffuse
forms could explain the different findings.
Impact of pain in health scleroderma quality of life
1301
100
80
*
SF-36 scores
*
*
60
Diffuse
*
Limited
40
20
0
PF
RP
BP
GH
VT
SF
RE
MH
PCS
MCS
FIG. 2. Comparison of SF-36 subscale scores in both diffuse (n ¼ 67) and limited SSc (n ¼ 22). Scores of each of the eight subscales of the
SF-36 can vary between 0 and 100, higher values reflecting better quality of life. PF, Physical functions, RP, role limitation-physical, BP,
bodily pain, GH, general health, VT, vitality, SF, social functions, RE, role limitation-emotional, MH, mental health, PCS, physical
component summary score, MCS, mental component summary score. The mean value for MCS and PCS in the general population is 50
with a S.D. of 10. Bars represent SE. *P < 0.05 (t-test). PF: P ¼ 0.009, RP: P ¼ 0.044, BP: P ¼ 0.024. NS for the other dimensions. PCS:
P ¼ 0.033, MCS: NS (t-test).
TABLE 4. PCS and MCS of the SF-36 according to the presence or absence
of various clinical manifestations
MCS
Absence
Presence
Absence
33 9
31 9
32 10
31 10
32 11
29 10
42 12
42 11
40 11
40 11
41 11
39 11
38 11
38 10
38 11
40 11
39 10
39 10
46 9
44 11
43 10
42 10
44 12
42 11
PCS, Physical component summary score; MCS, Mental component
summary score.
Clinical manifestations studied: Raynaud’s phenomenon (Raynaud)
crisis during the past week, digital lesions on examination (Digital),
Gastro-intestinal symptoms during the past week (Gastro-intestinal),
pulmonary involvement (Pulmonary), musculoskeletal involvement during
the previous week (Articular) and finger contracture (contracture).
All comparisons P < 0.0001, except for digestive (P ¼ 0.001) (t-test).
The mean value for MCS and PCS in the general population is 50 with
a S.D. of 10.
The QoL as assessed by the SF-36 appeared related to the
burden of clinical manifestations, in relation to the number of
clinical involvements, the functional disability and the pain,
whatever may be its cause. We found a high correlation between
pain and health-related QoL in SSc. Comparatively, the respective
correlations between the cutaneous involvement and pulmonary
function and QoL were moderate. Therefore, although it might be
a truism for any clinician, the effective control of the pain, which
can be related to the presence of either RP, digital ulcerations,
musculoskeletal or digestive involvement should constitute the
primary therapeutic goal to achieve a better QoL in SSc-treated
patients.
Our study carries a few limitations. One could argue that the
correlation between pain and the PCS of the SF-36 is directly
related to the item ‘bodily pain’, which constitutes one of the eight
SF-36 domains. However, the correlation between the pain VAS
and the PCS of the SF-36 was one of the highest correlations
observed in the present study. Moreover, it should be pointed
out that the correlations between pain VAS and each domain of
the SF-36 were high, not only with bodily pain (BP) domain
(R ¼ 0.71, P < 0.0001), but also with physical functionning (PF),
SF-36 summary scores
Raynaud
Digital
Gastro-intestinal
Pulmonary
Musculo-squelettal
Contracture
PCS
Presence
60
50
0
1
2
3
4
5
6
40
30
20
10
0
PCS
MCS
FIG. 3. Relation of physical and mental component summary
scores of the MOS-SF36 with the number of clinical involvement
in systemic sclerosis. Mean value of the physical component
summary score and mental component summary score of the
SF-36 related to the number of clinical involvement (Raynaud’s
phenomenon crisis during the past week, digital lesions on
examination, gastro-intestinal symptoms during the past week,
pulmonary involvement, musculoskeletal involvement during the
previous week and finger contracture). The mean value for MCS
and PCS in the general population is 50 with a S.D. of 10. Bars
represent SE. PCS: P < 0.0001, MCS: P ¼ 0.014 (ANOVA).
role physical (RP) and general health (GH), respectively, R ¼ 0.58,
0.54 and 0.57 (P < 0.0001).
This important finding for clinical practice appears as a
reminder of the importance of pain for the clinician in charge
of treating the numerous symptoms observed in SSc.
Although the number of patients in our study did not allow
to perform a multivariate analysis of the various determinants of
health-related QoL in SSc, the present work included the largest
number of patients with diffuse SSc studied today with the
primary aim to evaluate SSc QoL. Their scores were globally quite
lower than those reported by Danieli et al. [3] and Del Rosso et al.
[2] probably due to more severe forms of the disease, since
12 patients in our study were included in the Intensification et
Autogreffe dans les Maladies Auto-Immunes Résistantes
(ISAMAIR) study [12] and treated by haematopoiteic stem cell
transplantation for rapidly progressive diffuse SSc resistant to
C. Georges et al.
84 21
81 32
73 24
69 19
60 18
82 21
82 32
69 18
84
81
75
72
61
83
81
74
34 11
50 10
71 23
61 46
45 20
65 16
77 33
58 23
80 34
45 14
41 11
45 10
57 (35–80)
50 (0–100)
61 (41–76)
35 (24–45)
50 (35–60)
87 (62–100)
67 (0–100)
56 (38–68)
50 31
40 42
47 28
41 22
39 22
58 28
46 44
56 21
36 11
41 11
Physical functions (PF)
Role limitation-physical (RP)
Bodily pain (BP)
General health (GH)
Vitality (VT)
Social functions (SF)
Role limitation - emotional (RE)
Mental health (MH)
Physical component score (PCS)
Mental component score (MCS)
SF-36: PCS and MCS of the SF-36. A lower score indicates a poorer QoL. The mean values for MCS and PCS in the general population are 50 with a S.D. of 10.
General french population
(Leplege) [6] n ¼ 3656
General US population
Initial SF-36 study
(Ware) n ¼ 2472
Khanna [13]
(diffuse: n ¼ 196)
Del Rosso Arthritis [2]
(diffuse:n ¼ 9
limited: n ¼ 15)
Danieli [3] (diffuse:n ¼ 24
limited: n ¼ 52)
Present study
(diffuse: n ¼ 67
limited: n ¼ 22)
TABLE 5. Results of SF-36 scores of our study in comparison with three other SSc studies (Danieli [3], Del Rosso [2], Khanna [13]) and with normative data in general (US and French) population
(Ware, Leplege [6])
1302
prior treatment. In the study by Khanna et al. [13], 239 patients
were included with the primary aim to test the potential benefit
from relaxin treatment in SSc patients, and the evaluation of SSc
patients functional repercussion and QoL were not the primary
end point of this work [13]. Moreover, unlike in this study,
we chose to present the results of each eight subscales of SF-36,
which are of interest to precise the domains where QoL is altered
in SSc patients.
In conclusion, altered QoL in SSc is a major therapeutic
challenge for the clinician. The benefits in using selfquestionnaires’ analysis are important in daily clinical practice
since they appear to have a good correlation with the disease
severity. Our study yields to point out the impact of pain in
health-related QoL of patients with SSc.
The authors have declared no conflicts of interest.
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