Correlation between the SF-36 and CCVUQ Quality of Life Scales, Applied to Patients with Venous Ulcers: a cross-sectional study carried out in primary health care in Brazil
This study aimed to analyze the correlation between the QL scales SF-36 and CCVUQ, applied to people with VU assisted in Brazilian PHC units. This is an observational, cross-sectional study with a quantitative approach, carried out in 2020 in a center specialized in the prevention and treatment of chronic VU, which is a reference service for 29 PHC units in the city of Parnamirim, state from Rio Grande do Norte, Brazil. The study population consisted of patients who had active VU, treated at the PHC in the city of Parnamirim, which is located in the metropolitan region of the city of Natal, capital of the state of Rio Grande do Norte. We used the SF-36, which assesses eight domains and two dimensions of QoL, and the CCVUQ, a specific questionnaire to assess QoL in individuals with VU, which identifies four important divisions of health. To assess the internal consistency of the QoL scales (SF-36 and CCVUQ), we performed Cronbach's inferential analysis (α), using the following parameters: 0.30 < α ≤ 0.60 (low); 0.60 < α ≤ 0.75 (moderate); 0.75 < α ≤ 0.90 (high); α > 0.90 (very high). To analyze the correlation (r) between the scalar variables of both scales, the Spearman Rho Test was used. Their classification according to the levels of correlation was determined by the following parameters: r < 0.29 (weak); 0.29 > r < 0.49 (moderate); r > 0.50 (strong). The direction of the correlation was classified considering that the SF-36 scale indicates better QoL when it results in higher scores (increasing direction for better QoL), while the CCVUQ scale presents a decreasing sense to determine better QoL. Therefore, we called it “direct correlation” when r was negative and “opposite correlation” when r was positive. For all tests, we adopted a margin of error of 5% and a Confidence Interval (CI) of 95%, with a significance value of p<0.05. The final sample was n= 103. In the analysis, the correlation between the Domestic activities division (CCVUQ) aspect and the SF-36 Physical role functioning domains (r= -0.50/ p< 0.001) stood out as strong, and Physical functioning (r= -0.31/ p= 0.001), as moderate. The Social interaction division (CCVUQ) aspect showed moderate correlation with the SF-36 domains Physical role functioning (r= -0.43/ p< 0.001) and Physical functioning (r= -0.42/ p< 0.001). The Vitality domain (SF-36) showed a moderate correlation with aspects of the CCVUQ Cosmesis division (r= -0.32/ p< 0.001) and Emotional status Division (r= -0.36/ p< 0.001). We conclude that there was a direct correlation between the analyzed scales, which showed greater strength between the physical, functional and vitality aspects of the SF-36 and the domestic activities and social interaction of the CCVUC, data that imply the acceptance of our study hypothesis.
Steps to reproduce
The study population consisted of patients who had active VU, treated at the PHC in the city of Parnamirim, which is located in the metropolitan region of the city of Natal, capital of the state of Rio Grande do Norte. A non-probabilistic sample was obtained and selected for convenience. For the sample calculation, we adopted as reference the data provided by the local health agency, which had a total of 150 people with VU in the region studied during the study period. By adopting a 95% confidence interval and a 5% margin of error, the calculation resulted in n = 108. The result was obtained with the aid of an online calculator accessible at https://calculareconverter.com.br/calculo -sample/. Before the beginning of the collections, the researchers received qualification training as interviewers. They were undergraduate and graduate students in nursing, nutrition and medicine at the Federal University of Rio Grande do Norte. The collections were carried out through face-to-face interviews, with questions guided by the selected instruments and lasting approximately 60 minutes, in the period between August and October 2020. service, which were scheduled according to the institution's routine. No incentives or remuneration were offered to any of those involved in the study and there was no blinding of participants or researchers.
Conselho Nacional de Desenvolvimento Científico e Tecnológico
408535/2021-0 - Call CNPq/MCTI/FNDCT Nº 18/2021 - Faixa B - Grupos Consolidados