Quality of Life Questionnaire and Disease Severity Scale
Condition: Pelvic Congestion Syndrome
Study type: Observational

Summary: 
      There are currently no specific validated patient-centric tools for the clinical evaluation
      of patients with chronic pelvic venous disorders (CPVD). The study involves the development
      and validation of a questionnaire for the quality of life and a scale of disease severity for
      a patient with pelvic venous disease.
    

Detailed description: 
      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.

        1. 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.

        2. 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.

        3. 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.

        4. 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.
    

Intervention name(s): questionnaire responses
Intervention type(s): Other
Intervention description(s): questionnaire responses - Pelvic Varicose Veins Questionnaire (PVVQ) and Pelvic Venous Clinical Severity Score (PVCSS)
Observational model: Cohort
Time perspective: Retrospective
Sampling method: Probability Sample
Study population: 
        patients attending primary care
      
Keywords: quality of life questionnaire; chronic pelvic venous disorders; Pelvic Varicose Veins Questionnaire; pelvic congestion syndrome; validation; Pelvi Venous Clinical Severity Score