Cost-effectiveness Comparison Between Vaginal Versus Robotic Mesh Surgery for Apical Prolapse: Prospective, Cohort Study

Cost-effectiveness analysis: cost-effectiveness will be evaluated by comparing the vaginal approach with the robotic approach in term of incremental costs and incremental benefits (measured by QALYs gained).15 The incremental cost-effectiveness ratio (ICER) gives the marginal cost for each additional QALY gained by treating a patient using the robotic approach compared to the vaginal approach. To evaluate cost-effectiveness, the ICER must be compared with a reference willingness to pay (WTP) value. Sweden has no such official number, but the National Institute of Clinical Excellence (NICE) in the United Kingdom states a willingness to pay between 20,000 - 30,000 British pounds. If the ICER is below this threshold, the robotic approach will be considered cost-effective compared to the vaginal approach.

Grading of genital prolapse will be performed using the pelvic organ prolapse quantification (POP-Q) system which is a quantitative method for the assessment of vaginal topography and conforms to the standards recommended by the International Continence Society as described by Bump et al. (Am J Obstetrics Gynecology1996). Postoperative examinations are to be performed by the trial gynecologist with the patient in a supine position. Prolapse of the middle compartment equivalent to, or more, than 50% of the total vaginal length (TVL) (i.e. point C positioned at, or distal to, a point between the hymen and half the total vaginal length) is required for inclusion of a patient in the trial.

The 15D is a generic, comprehensive, self-administered, 15-dimensional, preference-based questionnaire. The 15D includes 15-dimensions: mobility, vision, hearing, breathing, sleeping, eating, speech (communication), excretion, usual activity, mental function, discomfort, depression, distress, vitality, and sexual functions. Each dimension has five descriptive levels to choose from. The 15D can be used as a profile and a single index score measure. The valuation system is based on the application of multi-attribute utility theory. The single index or utility score represents the generic health-related quality of life on a maximum value of 1 (full health) to lower bound of 0 (being dead). From the 15D, the generic minimal important change (MIC) can be calculated to indicate improvement or deterioration. Also, he quality adjusted life-year (QALY) is evaluated using the estimated 15D values preoperative and after surgery.

The PFDI-20 is both a symptom inventory and a measure of the degree of bother and distress (quality-of-life) caused by pelvic floor symptoms. It is a short-form version of the Pelvic Floor Distress Inventory. The questionnaire has been validated for use in pelvic reconstructive surgery and has proven sensitive to change.

The PFDI-20 includes 20 questions and 3 scales. Each of the 3 scales is scored from 0 (least distress) to 100 (greatest distress). The sum of the scores of these 3 scales serves as the overall summary score of the PFDI-20 and ranges from 0 - 300. The 3 scales include questions taken from the following widely used outcome measures: Urinary Distress Inventory - 6 questions, Pelvic Organ Prolapse Distress Inventory - 6 questions, and Colorectal-Anal Distress Inventory - 8 questions.

2D, 3D ultrasound mapping of prolapse mesh length in cm and mesh position from the urinary bladder neck and urethra as measured in cm. Further, to investigate if mesh position correlate to urinary incontinence and/or bladder emptying difficulties (urinary retention).

The EQ-5D questionnaire is used to assess the health condition. It is an instrument to be used to measure generic quality of life in a similar way to 15D, and will be used to measure adjusted quality of life (QALYs). Similar to the 15D, the questionnaire results are mapped to a single utility value.

The PFIQ-7 is an abridged version of the PFIQ and is used to assess life impact in women with pelvic floor disorders. The PFIQ-7 summary score is calculated by adding the scores from the 3 scales together to obtain the summary score (range 0-300).

The validated PISQ-12 is a condition-specific, 12-item questionnaire on sexual function, with ordinal response alternatives based on a 5-point Likert scale. The PISQ-12 correlates well with other sexual health questionnaires and has shown sensitivity to change after pelvic reconstructive surgery and predictability of scores using the unabridged PISQ (31 items). The specific questions can be combined to form a score where higher scores indicate better sexual function. The maximum PISQ-12 score is 48. The twelve questions of the PISQ-12 can be divided into three domains: behavioral-emotive, partner-related and physical.

VAS scale is a numeric rating scale and ranges from 0-10 (each digit is 1cm) where 0 indicates no and 10 indicates maximum, digits between 0-10 indicate degree of pain.

VAS scale is a numeric rating scale and ranges from 0-10 (each digit is 1cm) where 0 indicates no and 10 indicates maximum, digits between 0-10 indicate degree of severity of urinary incontinence. VAS scale for urinary incontinence: 0 indicate no urinary incontinence whereas 10 indicates maximal or severe urinary incontinence.

VAS scale is a numeric rating scale and ranges from 0-10 (each digit is 1cm) where 0 indicates no and 10 indicates maximum, digits between 0-10 indicate degree of satisfaction after mesh surgery. VAS scale for patient satisfaction: 0 indicates no satisfaction whereas 10 indicates maximal satisfaction.

VAS scale is a numeric rating scale and ranges from 0-10 (each digit is 1cm) where 0 indicates no and 10 indicates maximum, digits between 0-10 indicate degree of satisfaction. VAS scale for patient recommendation to other patients to undergo same surgery if they suffer apical prolapse: 0 indicates no recommendation whereas 10 indicates maximal recommendation.