Digital technologies for delivering multidisciplinary weight-management services: early value assessment

3.1 Evidence gaps and ongoing studies

Table 1 summarises the evidence gaps and ongoing studies that might address them. Information about evidence status is derived from the external assessment group's reports; evidence not meeting the scope and inclusion criteria is not included. The table shows the evidence available to the committee when the guidance was published.

3.2 Data sources

There are data collections with different strengths and weaknesses that could potentially support evidence generation. NICE's real-world evidence framework provides detailed guidance on assessing the suitability of a real-world data source to answer a specific research question.

NHS Digital's Community Services Data Set (CSDS) is a patient-level secondary uses dataset with clinical and operational data collected from publicly funded community services. It includes data from tier 2 and tier 3 weight-management service providers in England and could support evidence generation.

Patient‑level data from the CSDS can be linked to other datasets such as NHS Digital's Hospital Episode Statistics (HES) to support the evaluation of outcomes such as adverse events, further hospital appointments and referral to bariatric surgery. But all the outcomes needed to address the evidence gaps may not be available from the CSDS (for example, adherence data collected by the technology) and linking to other sources may not be possible. This may mean that additional data collection is needed.

The CSDS also informs the NHS National Obesity Audit. The audit data could provide supporting contextual information for evaluating cost effectiveness, such as current national uptake and accessibility of multidisciplinary weight-management services and assessment of changes over time.

The quality and coverage of real-world data collections are of key importance when used in generating evidence. Active monitoring and follow up through a central coordinating point is an effective and viable approach of ensuring good-quality data with broad coverage.

3.3 Evidence collection plan

To address the evidence gaps, a before and after implementation study or a prospective cohort study is suggested.

For either approach to evidence generation, the study should include people who have had a clinical assessment and are referred to multidisciplinary weight-management services for support. The study should compare outcomes between those whose weight-management service is delivered through the digital technologies and those who have treatment with standard care (in-person or remote treatment, or both) without implementation of the technologies. Data should be collected separately for people having:

For either study design, high-quality data on patient characteristics is needed to correct for any important differences between comparison groups (for example, using propensity score methods) and to assess who the technologies would not be suitable for. Important confounding factors should be identified with input from clinical experts during protocol development. It is important that people in either comparison group are followed up from a consistent start point at which they have been, or would have been, offered care through the digital technology. This should be in line with the intended use of the technology in the clinical pathway. Loss to follow up should be reported, with reasons, over the data collection period. Differences between self-reported and clinically measured weight-loss outcomes are also a potential source of bias, particularly if these vary between comparison groups, so a consistent measure should be used.

It is essential that appropriate safeguarding and risk management processes are in place when generating evidence. The pathway must allow for clinical review before referral to the technology programme. Also, any safety issues and related adjustments to medicine during the intervention must be flagged to the appropriate teams for onward referral and investigation. Composition of the multidisciplinary team must be reported and should include, or have access to, psychological support.

Data collection should follow a predefined protocol and quality assurance processes should be put in place to ensure the integrity and consistency of data collection. See NICE's real-world evidence framework, which provides guidance on the planning, conduct, and reporting of real-world evidence studies. This document also provides best practice principles for robust design of real-world evidence when assessing comparative treatment effects.

3.4 Data to be collected

To address the evidence gaps, the following data should be collected. For people who are taking weight-management medicine, baseline is when the medicine is prescribed. For people who are not taking weight-management medicine, baseline is when they are referred for multidisciplinary weight-management support:

3.5 Evidence generation period

This will be 4 years to allow for setting up, implementing the technologies, supplying and accessing medicine, data collection, analysis and reporting.