Lindblad Carina, Sandelin Kerstin, Petersson Lena-Marie, Rohani Camelia, Langius-Eklöf Ann
Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Karolinska University Hospital, Stockholm, Sweden.
Qual Life Res. 2016 Mar;25(3):753-60. doi: 10.1007/s11136-015-1114-4. Epub 2015 Aug 29.
To test the stability of the SOC scale over time and to test the stability of the latent construct in 417 breast cancer patients at the time of diagnosis, after 1 year and in a subsample (n = 80) also 2 and 3 years later.
The 13-item SOC scale was firstly tested with mean values and ICC over time and secondly explored with cross-sectional factor analysis, separately for two time points (baseline and after 1 year), followed by a longitudinal factor analyses.
Our results provide support for the stability over time (ICC 0.68, effect size 0.06). The cross-sectional factor analysis revealed a modified three-factor and a second-order factor model meeting criteria for goodness of fit. The longitudinal modified second-order factor model confirmed the construct stability character of the SOC scale with an acceptable goodness-of-fit criteria; X (2)/df = 2.91; GFI = 0.87; RMSEA = 0.07; CFI = 0.84; AIC = 962.3. The proportion of variance (R (2)) was 0.42.
The SOC scale is stable over time when applied to women with breast cancer. The longitudinal factor analysis gives support of a stable latent construct in the second-order factor model, allowing for merging all items to one scale reflecting the theoretical construct of SOC. Measurement errors between some items challenge future studies on alternative factor structures.
测试社会支持感（SOC）量表随时间的稳定性，并测试417名乳腺癌患者在诊断时、1年后以及一个子样本（n = 80）在2年和3年后潜在结构的稳定性。
首先用均值和组内相关系数（ICC）随时间对13项SOC量表进行测试，其次分别针对两个时间点（基线和1年后）进行横断面因素分析，随后进行纵向因素分析。
我们的结果支持随时间的稳定性（ICC 0.68，效应量0.06）。横断面因素分析揭示了一个修正的三因素和一个二阶因素模型，符合拟合优度标准。纵向修正二阶因素模型以可接受的拟合优度标准证实了SOC量表的结构稳定性特征；卡方值/自由度（X(2)/df）= 2.91；拟合优度指数（GFI）= 0.87；近似误差均方根（RMSEA）= 0.07；比较拟合指数（CFI）= 0.84；赤池信息准则（AIC）= 962.3。方差比例（R(2)）为0.42。
当应用于乳腺癌女性时，SOC量表随时间是稳定的。纵向因素分析支持二阶因素模型中潜在结构的稳定性，允许将所有项目合并为一个反映SOC理论结构的量表。一些项目之间的测量误差对未来关于替代因素结构的研究提出了挑战。
