Journal of Public Health Advance Access published December 23, 2014 Journal of Public Health | pp. 1–2
Correspondence Authors reply to comments made about our article ‘Food for thought’
Dear Editors,
Recruitment, inequalities and selection biases We undertook intensive recruitment in deprived neighbourhoods, accessed through practices within them. We also advertised for, and trained our cadre of lay health trainers (LHTs) from these deprived neighbourhoods, working with community groups and advertising widely locally, as that was the specific focus of the pilot. Indeed, we were recruiting our participants from among some of the most deprived wards in England. We looked beyond postcode as the sole measure of deprivation (one which would have classed most of our participants from among the most deprived populations in England). We explored individual deprivation markers as discussed in our paper. A key message is that those volunteering to take part represented a skewed sample of that deprived population, both in terms of those seeking training as LHTs and the participants identified as having a cardiovascular health risk and living in an area of high deprivation. The bias was towards the relatively better educated, more affluent and more change-motivated people within those populations. We do address these issues within the discussion section of the paper. This selection may
The LHT intervention This is detailed in the paper. In brief, participants were offered at least three face-to-face plus telephone support sessions from the LHTs. And responses were indeed varied. While some never responded to numerous calls from the LHTs to meet, others had up to seven face-to-face meetings plus telephone support. In both the LHT training and intervention design, we followed the national recommendations for the intervention design and frequency. It was not that participants were offered 1 or 2 sessions; the 1.25 value represents the average that was actually taken up despite case management by the LHTs. Our pragmatic evaluation was designed to explore the effect of routine delivery. ‘The intervention and training’ is described in detail in the Methods section of the paper. However, for editorial brevity some detail was pruned out. We actually did follow the emerging national framework as described by Lloyd et al. The training built upon that provided around the region and the training manuals being used at the time and involved local trainers in its development. The training itself involved a number of experienced practitioners with the relevant experience and training in motivational methods, behaviour change, etc. We hope that the title, methods and discussion make it clear that this was a pilot study. It was never intended to be powered as the definitive trial. We therefore hope that any inferences we make about the likely impact on dietary and associated outcomes of LHT inputs among this population
# The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: [email protected].
1
Downloaded from http://jpubhealth.oxfordjournals.org/ at University of Otago on November 14, 2015
We thank our colleagues for the interest they have shown in our research and its findings. We agree that evaluation of health trainer schemes presents many challenges. However, such difficulties should not be an excuse for not examining the issues. In particular, the perfect should not be used as the enemy of the good. And we hope that our experience, reported in detail in the paper, will provide useful material for a bigger, better randomized controlled trial (RCT), if and when that is successfully conducted. Meanwhile policymakers and commissioners have to base their strategic planning and service investment decisions on the totality of the evidence. We would humbly suggest that in spite of its imperfections, our study findings might offer many valuable insights. Taking each point in turn:
well reflect the barriers to wider participation raised by trial research procedures, over which we had little control. These barriers are not faced by evaluations of routine delivery through the national data set, but of course those evaluations are equally limited in their internal validity. We did not recruit from those referred to LHTs within the practices; as such, a sample would also be subject to other biases, because they will have been presenting with their own concerns to practitioners. Furthermore, at that time, the DNA rate to the LHT clinics in practices was high, and many patients were reluctant to be referred. We also referred to this point in our discussion. Locally therefore at least GP recruitment would be likely to have been even less likely to recruit those we wished to target.
2
CO R R ES PO N DE NC E
Conclusions We wish to confirm on behalf of all the authors that we have no vested interest in the findings described from our pilot trial, nor the success, or otherwise of the LHT programmes. However, we did wish to alert colleagues to the potential unintended consequence of widening health inequalities that might result from uncritically increasing investment in this approach. Finally, we are happy to echo the call for further robust evaluation, specifically looking at differential uptake and impact, and with sufficient follow-up. Controlled randomized designs will, of course, be essential. M.B. Gabbay1, M. Goodall1, S. Capewell1, P. Bowers2, L.A. Kennedy3, P. Byrne1, G.R. Barton4, A.M. Martindale1, on behalf of the Lay Health trainer Intervention Study (LHtIST) research group 1 University of Liverpool, Liverpool, UK 2 University of Manchester, Manchester, UK 3 University of Chester, Chester, UK 4 University of East Anglia, Norwich, UK Address correspondence to Mark Goodall, E-mail: [email protected] doi:10.1093/pubmed/fdu111
Downloaded from http://jpubhealth.oxfordjournals.org/ at University of Otago on November 14, 2015
are consequently and clearly tentative. The ‘well-conducted and controlled studies’ asked for in this letter will be able to build on the detailed pilot work we have presented. This however remains the only study to report these impacts compared with controls. Despite being underpowered, it therefore arguably represents relatively robust evidence compared with observational longitudinal studies lacking control data, however large they may be. We therefore remain concerned that many of the existing observational ‘evaluations’ are seriously flawed for these reasons, and others discussed in our paper. Our pilot describes the challenges of delivering the trial as originally intended (The ‘Intention to treat’ philosophy). It was peer reviewed by the MRC and partners within the NPRI research programme. We clearly highlight that we ended up recruiting an unrepresentative sample from within a deprived population, despite recruiting using standard trial methods for primary care participant recruitment from research active practices serving very deprived populations. The Health Trainer Intervention was designed and delivered in line with the national recommended approach. However, many participants were reluctant to engage with it, hence the relatively low average number of sessions. It was therefore true to the basis of the original model.
Correspondence Authors reply to comments made about our article ‘Food for thought’
Dear Editors,
Recruitment, inequalities and selection biases We undertook intensive recruitment in deprived neighbourhoods, accessed through practices within them. We also advertised for, and trained our cadre of lay health trainers (LHTs) from these deprived neighbourhoods, working with community groups and advertising widely locally, as that was the specific focus of the pilot. Indeed, we were recruiting our participants from among some of the most deprived wards in England. We looked beyond postcode as the sole measure of deprivation (one which would have classed most of our participants from among the most deprived populations in England). We explored individual deprivation markers as discussed in our paper. A key message is that those volunteering to take part represented a skewed sample of that deprived population, both in terms of those seeking training as LHTs and the participants identified as having a cardiovascular health risk and living in an area of high deprivation. The bias was towards the relatively better educated, more affluent and more change-motivated people within those populations. We do address these issues within the discussion section of the paper. This selection may
The LHT intervention This is detailed in the paper. In brief, participants were offered at least three face-to-face plus telephone support sessions from the LHTs. And responses were indeed varied. While some never responded to numerous calls from the LHTs to meet, others had up to seven face-to-face meetings plus telephone support. In both the LHT training and intervention design, we followed the national recommendations for the intervention design and frequency. It was not that participants were offered 1 or 2 sessions; the 1.25 value represents the average that was actually taken up despite case management by the LHTs. Our pragmatic evaluation was designed to explore the effect of routine delivery. ‘The intervention and training’ is described in detail in the Methods section of the paper. However, for editorial brevity some detail was pruned out. We actually did follow the emerging national framework as described by Lloyd et al. The training built upon that provided around the region and the training manuals being used at the time and involved local trainers in its development. The training itself involved a number of experienced practitioners with the relevant experience and training in motivational methods, behaviour change, etc. We hope that the title, methods and discussion make it clear that this was a pilot study. It was never intended to be powered as the definitive trial. We therefore hope that any inferences we make about the likely impact on dietary and associated outcomes of LHT inputs among this population
# The Author 2014. Published by Oxford University Press on behalf of Faculty of Public Health. All rights reserved. For permissions, please e-mail: [email protected].
1
Downloaded from http://jpubhealth.oxfordjournals.org/ at University of Otago on November 14, 2015
We thank our colleagues for the interest they have shown in our research and its findings. We agree that evaluation of health trainer schemes presents many challenges. However, such difficulties should not be an excuse for not examining the issues. In particular, the perfect should not be used as the enemy of the good. And we hope that our experience, reported in detail in the paper, will provide useful material for a bigger, better randomized controlled trial (RCT), if and when that is successfully conducted. Meanwhile policymakers and commissioners have to base their strategic planning and service investment decisions on the totality of the evidence. We would humbly suggest that in spite of its imperfections, our study findings might offer many valuable insights. Taking each point in turn:
well reflect the barriers to wider participation raised by trial research procedures, over which we had little control. These barriers are not faced by evaluations of routine delivery through the national data set, but of course those evaluations are equally limited in their internal validity. We did not recruit from those referred to LHTs within the practices; as such, a sample would also be subject to other biases, because they will have been presenting with their own concerns to practitioners. Furthermore, at that time, the DNA rate to the LHT clinics in practices was high, and many patients were reluctant to be referred. We also referred to this point in our discussion. Locally therefore at least GP recruitment would be likely to have been even less likely to recruit those we wished to target.
2
CO R R ES PO N DE NC E
Conclusions We wish to confirm on behalf of all the authors that we have no vested interest in the findings described from our pilot trial, nor the success, or otherwise of the LHT programmes. However, we did wish to alert colleagues to the potential unintended consequence of widening health inequalities that might result from uncritically increasing investment in this approach. Finally, we are happy to echo the call for further robust evaluation, specifically looking at differential uptake and impact, and with sufficient follow-up. Controlled randomized designs will, of course, be essential. M.B. Gabbay1, M. Goodall1, S. Capewell1, P. Bowers2, L.A. Kennedy3, P. Byrne1, G.R. Barton4, A.M. Martindale1, on behalf of the Lay Health trainer Intervention Study (LHtIST) research group 1 University of Liverpool, Liverpool, UK 2 University of Manchester, Manchester, UK 3 University of Chester, Chester, UK 4 University of East Anglia, Norwich, UK Address correspondence to Mark Goodall, E-mail: [email protected] doi:10.1093/pubmed/fdu111
Downloaded from http://jpubhealth.oxfordjournals.org/ at University of Otago on November 14, 2015
are consequently and clearly tentative. The ‘well-conducted and controlled studies’ asked for in this letter will be able to build on the detailed pilot work we have presented. This however remains the only study to report these impacts compared with controls. Despite being underpowered, it therefore arguably represents relatively robust evidence compared with observational longitudinal studies lacking control data, however large they may be. We therefore remain concerned that many of the existing observational ‘evaluations’ are seriously flawed for these reasons, and others discussed in our paper. Our pilot describes the challenges of delivering the trial as originally intended (The ‘Intention to treat’ philosophy). It was peer reviewed by the MRC and partners within the NPRI research programme. We clearly highlight that we ended up recruiting an unrepresentative sample from within a deprived population, despite recruiting using standard trial methods for primary care participant recruitment from research active practices serving very deprived populations. The Health Trainer Intervention was designed and delivered in line with the national recommended approach. However, many participants were reluctant to engage with it, hence the relatively low average number of sessions. It was therefore true to the basis of the original model.
