Validity and reliability of the Perceived Stress Scale among cancer survivors / 中国心理卫生杂志

ABSTRACT

Objective:To test the validity and reliability of the Perceived Stress Scale-14 items (PSS-14) applied in cancer survivors.Methods:Totally 652 cancer survivors (patients who had finished active treatments and were in convalescence) were selected and a field questionnaire survey was conducted among them.Exploratory factor analysis and confirmatory factor analysis were performed to test the construct validity of PSS-14.Correlation between the two dimensions (discriminant validity) and correlation between stress and quality of life were analyzed to further test its validity.The intemal consistency reliability,split-half reliability,retest reliability and sensitivity analysis were adopted to test the reliability of PSS-14.Results:Two common factors were extracted in the exploratory factor analysis.The cumulative percentage of variance explained was 60.8％.The index of confirmatory factor analysis wereTLI =0.92,CFI =0.93,SRMR =0.07,RMSEA =0.08.The correlation coefficient between the two dimensions of PSS-14 was-0.16 (P ＜0.001).The correlation coefficients between the score of PSS-14 and each dimension of EORTC QLQ-C30 were 0.24-0.55 (P ＜ 0.001).The Cronbach α coefficients of the whole scale and the two dimensions named "perceived coping ability" and "perceived distress" were 0.78,0.91 and 0.88 respectively.After the scale was split into two parts,the Cronbach α coefficients of each part were 0.66 and 0.60.The Spearman-Brown coefficient was 0.79.The Guttman split-half coefficient was 0.79.After one item was removed from the scale each time,the Cronbach a coefficients of the remaining items varied from 0.75 to 0.77.The retest reliability of the whole scale and the two dimensions were 0.89,0.86 and 0.85 respectively.Conclusion:PSS-14 shows favorable validity and reliability,suggesting the utility to assess stress of cancer survivors as a self-administered inventory.