Cost-effectiveness of ISBCS vs. DSBCS

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effectiveness and costs of immediately sequential bilateral cataract surgery (ISBCS) compared to delayed sequential bilateral cataract surgery (DSBCS) in order to determine whether ISBCS is an effective and cost-effective alternative to DSBCS.

Detailed Description
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With an estimated number of 180,000 cataract extractions per year in the Netherlands, cataract surgery is one of the most frequently performed types of surgery. The majority of patients suffer from bilateral cataract and while cataract surgery of one eye is effective in restoring functional vision, second-eye surgery leads to further improvement in health-related quality of life. Currently, most patients undergo cataract surgery in both eyes on separate days as recommended in national guidelines, referred to as delayed sequential bilateral cataract surgery (DSBCS). An alternative procedure involves cataract surgery of both eyes on the same day, but as separate procedures, known as immediately sequential bilateral cataract surgery (ISBCS). Potential benefits of ISBCS include less time between surgeries, a faster total recovery period and lower costs. Potential risks, however, are complications of cataract surgery in general, most importantly the risk of endophthalmitis and refractive surprise. In ISBCS, both eyes are at risk at the same time, while in DSBCS both eyes are exposed to these risks consecutively. Since there is no consensus yet about the role of ISBCS in current regular practice, further investigation of functional and surgical outcomes and cost-effectiveness of ISBCS compared to DSBCS is required. Therefore, the purpose of this study is to evaluate the effectiveness and costs of ISBCS compared to DSBCS, in order to determine whether ISBCS is an effective and cost-effective alternative to DSBCS.

Official Title
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Cost-effectiveness of Immediately Versus Delayed Sequential Bilateral Cataract Surgery (ISBCS vs. DSBCS)

Conditions
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Bilateral Cataract

Intervention / Treatment
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* Procedure: ISBCS
* Procedure: DSBCS


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Bilateral cataract Indication for bilateral cataract surgery Expected uncomplicated surgery Exclusion Criteria: Inability to comply with study procedures or to complete follow-up / Dutch questionnaires. Non-routine cataract surgery Cognitive or behavioural conditions that might interfere with surgery Cataract surgery with premium IOL implantation Conditions that increase the risk of endophthalmitis (e.g. current ocular/adnexal/periocular infections, immune-compromised, iodine allergy) Factors that increase the risk of refractive surprise (e.g. axial lengths <21mm or >27mm, difference between eyes of >1.5mm, abnormal keratometry readings, previous refractive surgery) Conditions that increase the risk of corneal edema Factors that increase the risk of complicated surgery (e.g. previous surgery, trauma, anatomical abnormalities) Sight-threatening comorbidity, Glaucoma or IOP > 24mmHg, Uveitis, Diabetes with diabetic retinopathy and macular edema

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: ISBCS<br>The intervention group will undergo cataract surgery of both eyes on the same day (ISBCS) | Procedure: ISBCS<br>* The intervention group will undergo cataract surgery in both eyes on the same day (ISBCS)<br>|
| Active Comparator: DSBCS<br>The usual care / control group will undergo cataract surgery of both eyes on separate days, with a time period of at least two weeks between surgeries (DSBCS). | Procedure: DSBCS<br>* The usual care / control group will undergo cataract surgery in both eyes on separate days, with a time period of at least two weeks between surgeries.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Refraction: deviation of 1.0 D from target refraction | Proportion of patients in both treatment groups with a postoperative refraction in the second eye that deviates 1.0 diopters (D) from target refraction | Four weeks post-operatively | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Refraction: deviation of 0.5 D from target refraction | Proportion of patients in both treatment groups with a postoperative refraction in the second eye that deviates 0.5 diopters (D) from target refraction | Four weeks post-operatively | 
| Change in visual acuity | Visual acuity will be measured by ETDRS letter charts | Baseline, 1 week after first-eye surgery and 4 weeks after second-eye surgery | 
| Complications | The incidence of intraoperative and postoperative complications | Intraoperatively and up to 4 weeks after second-eye surgery | 
| Patient reported outcome measures (PROMs): NEI VFQ-25 | Patient satisfaction and vision-specific quality of life as measured by National Eye Institute Visual Function Questionnaire (NEI VFQ-25). | Baseline and 3 months postoperatively | 
| Patient reported outcome measures (PROMs): Catquest | Patient satisfaction and vision-specific quality of life as measured by Catquest questionnaire. | Baseline and 3 months postoperatively | 
| Patient reported outcome measures (PROMs): HUI3 | Health-related quality of life as measured by HUI3 (Health Utility Index Mark 3) questionnaire. | Baseline, 1,4 weeks and 3 months postoperatively | 
| Patient reported outcome measures (PROMs): EQ-5D-5L | Health-related quality of life as measured by EQ-5D-5L questionnaire. | Baseline, 1,4 weeks and 3 months postoperatively | 
| Quality Adjusted Life Years (QALYs) | Calculated based on generic health-related quality of life, using the EQ-5D-5L and HUI-3 questionnaires | Baseline until 3 months postoperatively | 
| Costs per patient | Cost per patient, including valuation of resource use by using the Dutch guidelines for cost-analyses or cost prices provided by the medical center. | Baseline until 3 months postoperatively | 
| Incremental cost-effectiveness ratios (ICERs): QALY | Evaluation of cost-effectiveness by using calculated costs per quality-adjusted life years (QALYs) | Baseline until 3 months postoperatively | 
| Incremental cost-effectiveness ratios (ICERs): Target refraction | Calculated costs per patient with a postoperative refraction within 1.0 D of target refraction | Baseline until 3 months postoperatively | 
| Incremental cost-effectiveness ratios (ICERs): NEI VFQ-25 | Calculated costs per clinically improved patient on the NEI VFQ-25 questionnaire | Baseline until 3 months postoperatively | 
| Incremental cost-effectiveness ratios (ICERs): Catquest | Calculated costs per clinically improved patient on the Catquest questionnaire | Baseline until 3 months postoperatively | 
| Incremental cost-effectiveness ratios (ICERs): Visual acuity | Calculated costs per patient with clinical improvement in (un)corrected distance visual acuity | Baseline until 3 months postoperatively | 
| Budget impact | Reported as a difference in costs. Different scenario's will be compared to investigate the impact of various levels of implementation (e.g. 25%, 50%, 75% of eligible patients). | Baseline until 3 months postoperatively |