Use of routinely collected data in a UK cohort of publicly funded randomised clinical trials

Introduction

Routinely collected data about health in medical records, registries and hospital activity statistics is now routinely collected in an electronic form. Progress in achieving connectivity, data linkage and security now offers the possibility of better use of this data for research purposes. For example, recent evidence shows the utility of long-term follow-up of trial patients by linkage to routinely collected health data (RCHD) sources (Fitzpatrick et al., 2018). Innovative data-enabled study designs can answer pressing knowledge gaps in research evidence. However, the extent to which such sources of data are now being routinely employed in research to deliver efficient clinical trials, potentially at a wide scale, is unclear.

The aim of this study was to ascertain current practice amongst a United Kingdom (UK) cohort of recently funded and ongoing randomised controlled trials (RCTs) in relation to sources and use of routinely collected outcome data. We chose NIHR HTA because they are a major source of funding for investigator-led publicly funded clinical trials within the UK in an NHS setting. We define RCHD to be data collected without specific a priori research questions developed prior to using the data for research.

Methods

Results

Figure 1 shows the study flow diagram. 279 records were identified through database searching and screened for inclusion. 22 were non-RCTs, 1 was a completed RCT, 30 were RCTs but no protocol was available and 10 were unclear. Of the remaining 216 NIHR HTA trials with a protocol available for further study, 102 (47%) planned to use RCHD for at least one outcome.

Figure 1. PRISMA flow diagram.

Table 1 shows the reasons for collecting trial outcome data from routine sources from the 102 eligible trials. The RCHD source was the sole source of outcome data for at least one outcome in 46 (45%) of those 102 trials (categories 3, 4 and 6 in Table 1). In five of these 46 protocols there was reference to prior feasibility work confirming aspects of the quality of the data to be sufficient for the main trial. Of the 102 trials, 14 (categories 7a-7d in Table 1) planned to assess the feasibility of using the RCHD sources during the trial, although details of the assessment were often lacking. Raw data for Figure 1 and Table 1 and Table 2 are available (see Underlying data, McKay et al. (2020)).

Table 2 shows the RCHD sources of outcome data to be used in these 46 studies. The most frequent RCHD sources are Hospital Episode Statistics (HES) and Office for National Statistics (ONS), with the most common outcome data to be extracted being on mortality, hospital admission, and health service resource use (see Underlying data, Data Set 5; McKay et al. (2020)). The full list of RCHD sources is given in Extended data, Supplementary Table 1 (McKay et al., 2020).

Discussion

Our study has found that around half of publicly funded trials in a UK cohort (NIHR HTA funded trials that had protocol available) plan to collect outcome data from RCHD sources. A cohort of 189 RCTs published since 2000, the majority of which were carried out in North America (McCord et al., 2019), found this figure to be higher at 84%, however, they identified their cohort as those mentioning ‘EHR’ in some way, i.e. a selected cohort, whereas ours is an unselected cohort so they are not comparable due to the selectivity of the samples.

Very few trial teams described any assessments of data quality from RCHDs in the protocol. Work is ongoing that should determine whether such information should be reported in the trial publication (Kwakkenbos et al., 2018). An extension to the SPIRIT guidelines for trials using RCHD is soon to be initiated, and will determine whether this information should be included in the trial protocol. As a minimum, it is recommended that trialists provide evidence in any funding application about the quality of the data from the RCHD source.

Data availability