Quality of Life Questionnaire and Disease Severity Scale

This retrospective study will include patients with pelvic varicose veins seen between 2018 and 2020.

2 groups of patients will be formed. The main group will be women with verified CPVD, the comparison group - 93 participants without signs of CPVD.

All patients will respond to the previously developed Pelvic Varicose Veins Questionnaire (PVVQ) and Pelvic Venous Clinical Severity Score (PVCSS) as submitted questionnaires.

Validation of the PVVQ questionnaire and the PVCSS scale will be carried out in accordance with the methodology for studying the quality of life and clinical scales in accordance with international standards. The main psychometric properties of both instruments in terms of validity, reliability and sensitivity will be assessed.

The validation protocol will include certain steps: 1) pre-testing, 2) assessing the reliability of the questionnaire, 3) assessing the validity, 4) assessing the sensitivity.

• Preliminary testing. For preliminary testing, patients will fill out questionnaires, followed by finding out how clear the questions asked are, how accurate and ethical the formulations are, in their opinion. The convenience of working with the questionnaire from the point of view of the research doctor will also be assessed.
• Reliability assessment. The reliability assessment will be carried out according to three criteria - internal consistency, discriminant validity and internal consistency.

To assess the degree of internal consistency, the Cronbach's alpha coefficient will be used, which is calculated by the formula: α = N * r / (1 + r * (N - 1)), where N is the number of components under study, r is the average correlation coefficient between the components. The study will assess the reliability of the questionnaire and the scale as a whole, as well as the impact on the overall reliability of each individual domain. Domain correlation will be assessed using Spearman's rank correlation method (r).

To assess discriminant validity, the level of quality of life and disease severity of patients with VBT will be compared with similar levels of healthy participants.

Assessment of internal consistency will be performed by retesting stable patients without treatment after 14 days, followed by calculation of Cronbach's alpha.

• Assessment of validity. To assess the validity, the reliability of the construct will be studied by determining the criterion validity, i.e. identifying the correlation coefficient or relationships between the scales of both questionnaires with some external criterion. The scales of the SF-36 questionnaire will be used as external criteria for assessing the quality of life, and elements of visual analogue scales will be used to assess the severity of the disease.

To study the degree of representation of the studied psychological construct in the test results, both types of construct validity will be determined: convergent and discriminant.

• Sensitivity assessment. To assess the sensitivity, a comparison of the indicators of the questionnaire questionnaires at the points before treatment and 2 months after the treatment will be carried out.

Based on this examination of the data, objective information on the validity, reliability and sensitivity of PVVQ and PVCSS will be obtained.

Inclusion criteria

• presence of PVV;
• completed Patient Informed Consent Form;
• age from 18 to 70 years;
• ability to understand and answer the questions of the proposed questionnaire.

Exclusion criteria

• absence of confirmed PVV;
• lack of Patient Informed Consent Form;
• under the age of 18 or over 70 years old;
• pregnancy at any stage and 12-month postpartum period;
• presence of a gynecological or other concomitant (urological, neurological, procto-logical, etc.) significant pathology that has similar clinical symptoms with CPVD and re-quires specific treatment;
• presence of severe concomitant gastrointestinal or hematopoietic system pathology, terminal stages of cardiovascular, respiratory, renal and hepatic failure, stage IV malignant tumor, obliterating diseases of lower limbs arteries;
• dementia and other mental disorders that limit the ability to understand the essence of the research, fill out Patient Informed Consent Form and answer the questionnaire