Development and validation of the 10-item Social Provisions Scale (SPS-10) Japanese version

Abstract


(1980 words) Introduction
Having positive supportive relationships with family and friends, who can listen and help in the event of problems, has a beneficial effect on maintaining psychological health.A large number of studies have investigated the link between social support and depressive symptoms [1].Clara et al. reported that having higher perceived available social support was associated with fewer depressive symptoms [2].Several prospective studies have found that positive support from family members can facilitate recovery from a major depressive episode [3,4].Some studies have reported that greater social support deficits predict subsequent higher depressive symptomatology [5,6].Therefore, in research studies associated with mental health and social support, it is important to develop a scale that can appropriately measure social support and be compared internationally.
The Social Provisions Scale (SPS) developed by Cutrona and Russell [7] is one of the most widely used measures of perceived social support.The SPS is a 24-item self-report questionnaire, and has the following six subscales that measure six types of social provision: attachment, reassurance of worth, reliable alliance, social integration, guidance, and opportunity for nurturance.The measure has good psychometric properties in term of reliability and predictive, convergent and construct validity [7,8].The measure has been used in diverse populations such as college students [9], spouses of cancer patients [10], and patients with multiple sclerosis [11].The 10-item Social Provisions Scale (SPS-10) is a short version of the original SPS and was developed by Iapichino et al. [12] in Italian.The reliability and validity of the Italian SPS-10 are excellent.
The aim of the present study was to develop the SPS-10 Japanese version and to examine its reliability and validity.

Subjects and Procedure
The study population consisted of mothers of patients with an eating disorder.The mothers of patients with eating disorder were selected as subjects because the family burden of patients with eating disorders is high.Potential subjects were recruited from four family self-help groups of patients with eating disorders in the community and one university hospital in Japan from July 2017 to August 2018.Inclusion criteria were: the mother of a female patient who met the criteria for the clinical diagnosis of an eating disorder as determined by a physician in a hospital; the patient with an eating disorder was aged between 16 and 50 years; and the patient's mother was aged between 30 and 85 years.
We gave participants of four family self-help groups of patients with eating disorders in the community and one university hospital a leaflet with an explanation of the purpose and procedure of the study.After receiving permission from mothers and the home address, we mailed questionnaires to their homes and enrolled them in the study when their completed questionnaires were returned.

SPS-10
The Social Provisions Scale (SPS) assesses the degree to which an individual perceives that his/her social network provides different kind of social support, including opportunities for the individual to provide support.[7] The original SPS is a self-report questionnaire that includes 24 items rated on a four-point Likert-type scale.The scale includes the following six subscales based on Weiss's social provisions theory [13]: reliable alliance, attachment, opportunity for giving support to others, social integration, reassurance of worth, and guidance.
Iapichino et al. [12] developed a short version of the SPS, which consists of 10 items (SPS-10).The SPS-10 retains the following five of the six original SPS subscales: attachment (emotional support), social integration, reassurance of worth, reliable alliance (material support) and guidance.In the original SPS, each subscale has four items: two positively worded items describing the presence of a type of support and two negatively worded items assessing the absence of a type of support.The SPS-10 has only negatively worded items, and the total score on the SPS-10 ranges from 10 to 40 [12].A higher total score indicates stronger perceived provision of social support.

Translation
Two native Japanese speakers translated into Japanese independently the 10 items of the English version of the original SPS that corresponded to the items in the Italian version of the SPS-10.One of the translators was a psychiatrist (NW), while the other was a psychiatric nurse (FK).The two translators met to discuss the forward-translated Japanese version.Two other translators who were blind to the original version translated the Japanese-translated version back into English in order to ascertain whether the translated questions communicate comparable meanings.One of the translators spoke both Japanese and English, while the other was a Japanese science translator specializing in psychiatry and psychology.Finally, the original author of the SPS-10 Italian version (PR) confirmed semantic and conceptual equivalence among the SPS-10 Italian version and the original English version and the backtranslated English version.The SPS-10 Japanese version is a 10-item self-report questionnaire with higher scores indicating higher social support experience.Each item is rated on a fourpoint Likert-type scale ranging from 1 to 4.

UCLA Loneliness Scale (ULS)
The ULS is a self-report questionnaire developed by Russell [14].The ULS contains 20 items, with higher scores indicating higher loneliness experience.The reliability and validity of the Japanese version of the ULS are excellent [15].Cronbach's α coefficient of reliability in this study was 0.90.

Beck Depression Inventory (BDI-II)
The BDI-II is a 21-item self-report instrument that assesses the presence and severity of symptoms of depression [16].The reliability and validity of the Japanese version of the BDI-II are excellent [17].Cronbach's α coefficient of reliability in this study was 0.92.

K6
We used the K6 questionnaire, a six-item self-report questionnaire that was developed to screen for DSM-IV defined depression and anxiety disorders within 30 days prior to its administration.A validation study of the Japanese version of the K6 questionnaire showed that the K6 has excellent validity [18].Cronbach's α coefficient of reliability in this study was 0.86.

Statistical analysis
Descriptive data analysis was conducted by calculating frequencies, median, mean scores, and standard deviation.To determine the construct validity of the SPS-10 Japanese version, we calculated Pearson's correlation coefficients between the total score on the SPS-10 Japanese version and the scores of the other scales.The internal consistency of the SPS-10 Japanese version was tested using Cronbach's α coefficient.In addition, to investigate the structural validity of the scale, confirmatory factor analysis of items was carried out.Each item was specified to load onto only the factor it was designed to measure, with correlations among the five factors freely estimated.In order to test the goodness of fit of the model, four approximate fit indices were considered: comparative fit index (CFI); goodness fit index (GFI); adjusted GFI (AGFI), with values > 0.8 and 0.9 indicating acceptable and excellent fit, respectively; and root mean square error of approximation (RMSEA) with values < 0.05 and 0.08 indicating close and reasonable fit, respectively.Statistical analysis was performed using SPSS Statistics version 22 and SPSS Amos version 26.

Ethical Issues
This study was approved by the Ethics Review Committee of Nagoya City University Graduate School of Medical Sciences, Japan (Ref: No 60-17-0001), and was conducted in accordance with the principles stated in the Helsinki Declaration.The study is registered at University Hospital Medical Information Network under number UMIN000031698 (March 9, 2018).Participants were given an explanation of the purpose and the procedure of the study using a leaflet.After receiving permission from mothers and the home address, we mailed questionnaires to their homes and enrolled them in the study when their completed questionnaires and their written consent were returned.

Results
The study sample consisted of 72 mothers of patients with an eating disorder who completed the SPS-10 Japanese version questionnaire, ULS, BDI-II and K6.The disease duration of the patients was 7.6 [standard deviation (SD)=5.5]years.Table 1 summarizes the demographic characteristics and clinical status of the subjects.Table 2 shows the frequency distribution of the SPS-10 Japanese version scores, that was slightly asymmetric.
Cronbach's α for the overall scale was 0.89, denoting a good internal consistency.The total score of the SPS-10 Japanese version had significant negative correlations with three other scales: r=-0.79 (Pearson correlation coefficient) (p<0.01) with the ULS, r=-0.44 (p<0.01) with the BDI-II, and r=-0.39 (p<0.01) with the K6.
We conducted a confirmatory factor analysis assuming a five-factor model with the five subscales of attachment, social integration, reassurance of worth, reliable alliance and guidance (Figure 1).The confirmatory factor analysis model showed satisfactory goodness of fit indices except for the RMSEA (CFI=0.894,GFI=0.871,AGFI=0.716, and RMSEA=0.14).All items had high loadings on the respective factors, ranging from 0.48 to 0.88.

Discussion
The present study is the first to develop the SPS-10 Japanese version and to examine its reliability and validity.The results indicated that the SPS-10 Japanese version possesses excellent psychometric properties (Pearson's correlation coefficient between the SPS-10 Japanese version and the UCLA loneliness scale was -0.79).The participants of this study were mothers of patients with eating disorders whose mean duration of treatment for their disease was 7.6 (SD=5.5)years.The family burden of patients with eating disorders is high because family members are over-involved in behavioral and emotional aspects [19].The participants of this study had somewhat worse mental health status than the general population in Japan [K6 scores in our participants 6.9±4.2 versus 3.6±3.9[20]; BDI-II score in our participants 14.1 ± 9.7, indicating mild depressive symptoms], and more than half of them had received counseling themselves (Table 1).Therefore, the participants of this study needed some support and might be an appropriate group to assess the validity and reliability of the SPS-10 Japanese version which evaluates social support.
The frequency distribution of the scores on the SPS-10 Japanese version was similar to that of the SPS-10 Italian version (Table 2).The value of Cronbach's α obtained in the present study was 0.89 and was similar to the internal consistency coefficient obtained in the Italian study on the SPS-10 (0.809) [12].This lends support for excellent internal consistency and reliability of the SPS-10 Japanese version and suggests that this scale can be used in Japanese people.
In the present study, the total score on the SPS-10 Japanese version was strongly negatively correlated with the ULS scores, which measures the degree of loneliness, and was moderately negatively corelated with the BDI-II score, which measures the degree of depression/anxiety.Weiss [13] reported that people need six types of social provisions, and if some type is deficient, people are at risk for experiencing social and/or emotional loneliness.This loneliness could subsequently lead to distress, tension, and disengagement, along with depression.Our findings suggest good construct validity of the SPS-10 Japanese version.
We performed confirmatory factor analysis using the five factors of the SPS-10 Italian version [12] and confirmatory factor analysis model had a good fit to data.All items had sufficient factor loading on their respective factors (0.48-0.88).These results suggest that the structure of the SPS-10 Japanese version was consistent.Our findings suggest that the SPS-10 Japanese version has good reliability and validity as a measure of social support in the Japanese population.
In conclusion, the results of this study supported the construct, structural validity and reliability of the SPS-10 Japanese version in a sample of Japanese women.The SPS-10 Japanese version is simple and easy to use.We demonstrated the potential utility of the SPS-10 Japanese version as a screening tool to assess social support in people experiencing difficulties in Japan.

Supplementary Files
This is a list of supplementary les associated with this preprint.Click to download. Table12BMC.pdf

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