This well-conducted randomised trial provides evidence of the likely cost-effectiveness of both face-to-face physiotherapy and breathing retraining delivered using a DVD and booklet. Limitations include the time frame used, the reliance of the cost-effectiveness estimates on a single trial and the restriction of the
TABLE 47 Incremental cost per AQLQ score improvement (ICER) based on imputed data
Treatment arm Cost (£), mean (95% CI) Difference in costs (£), mean (95% CI) Difference in AQLQ score, mean (95% CI) Incremental cost (£) per AQLQ score improvement (95% CI)
Usual care (n= 246) 380 (310 to 459) DVD (n= 244) 296 (228 to 374) Physiotherapy (n= 120) 334 (299 to 269)
Physiotherapy vs. usual care –45 (–134 to 33) 0.23 (0.06 to 0.40) –400 (–1545 to 106) DVD vs. usual care –83 (–187 to 12) 0.26 (0.11 to 0.41) –340 (–986 to 52)
DOI: 10.3310/hta21530 HEALTH TECHNOLOGY ASSESSMENT 2017 VOL. 21 NO. 53
© Queen’s Printer and Controller of HMSO 2017. This work was produced by Thomas et al. under the terms of a commissioning contract issued by the Secretary of State for Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should be addressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK.
TABLE 48 Costs, QALYs and incremental cost per QALY (ICERs) using bootstrap methods based on imputed data
Treatment arm Cost (£), mean (95% CI)
Incremental cost
(£), mean (95% CI) QALYs, mean (95% CI)
Incremental QALYs,
mean (95% CI) ICER (£/QALY) (95% CI)
Usual care 377 (310 to 459) 0.767 (0.738 to 0.79)
Physiotherapy 333 (299 to 369) –41 (–134 to 33) 0.771 (0.735 to 0.807) 0.005 (–0.039 to 0.05) –671 (–14,269 to 13,814) DVD 293 (228 to 374) –83 (–187 to 12) 0.788 (0.764 to 0.811) 0.022 (–0.013 to 0.058) –2754 (–17,739 to 12,017) DVD vs. physiotherapy 40 (–43 to 116) 0.017 (–0.025 to 0.06) –941 (–12,260 to 11,620)
Treatment arm Cost (£), mean (95% CI)
Incremental cost (£) (95% CI)
QALYs adjusted for baseline QoL, mean (95% CI)
Incremental adjusted QALYs (95% CI)
ICER (£/adjusted QALY) (95% CI) Usual care 377 (310 to 459) 0.767 (0.741 to 0.788) Physiotherapy 333 (299 to 369) –41 (–134 to 33) 0.773 (0.74 to 0.805) 0.007 (–0.033 to 0.047) –877 (–15,555 to 18,573) DVD 293 (228 to 374) –83 (–187 to 12) 0.787 (0.765 to 0.807) 0.02 (–0.011 to 0.053) –3057 (–18,877 to 10,864) DVD vs. physiotherapy 40 (–43 to 116) 0.014 (–0.023 to 0.052) –1145 (–14,982 to 9843) Note
The mean incremental costs and QALYs and ICERs between two treatment arms are not directly derived from the mean cost and mean QALYs in each group because of the bootstrap methods used. ECONOMIC EVALUATION NIHR Journals Library www.journalslibrary.nihr.ac.uk
costing perspective to the NHS. Although longer-term follow-up would be desirable, it seems likely that patients who have been able to improve their QoL using breathing retraining would continue to apply the techniques that they have learned. If so, the benefits recorded here may have been understated. Although cost-effectiveness should ideally be based on the totality of evidence, such as a meta-analytical estimate of effect size, we note similar results for the one similar trial of breathing exercises in asthma.17Our adoption
of a NHS, as opposed to a societal, perspective was based on the returns from a questionnaire, which indicated that few costs fell outside the NHS.
The cost/AQLQ analysis favoured both the DVD intervention and the face-to-face physiotherapy intervention compared with usual care, with the DVD intervention achieving equivalent outcomes to the face-to-face physiotherapy intervention at a lower cost. The cost/QALY analysis showed similar results for the DVD and face-to-face physiotherapy comparisons with usual care, albeit based on small non-significant differences in outcomes. Both interventions dominated usual care. The DVD intervention had similar outcomes to the
– 200 – 300 – 0.05 0.00 0.05 0.10 – 100 Cost (£) 100 0 QALYs 95% CI prediction ellipse Cost
FIGURE 6 Scatterplot of the joint distribution of the incremental mean cost from a NHS perspective and mean QALYs adjusted for baseline QoL over 12 months based on the imputed data: 95% CI ellipse DVD arm compared with the usual-care arm.
– 200 – 0.05 0.00 0.05 – 100 Cost (£) 100 0 QALYs 95% CI prediction ellipse Cost
FIGURE 7 Scatterplot of the joint distribution of incremental mean cost from NHS perspective and mean QALYs adjusted baseline QoL over 12 months based on the imputed data: 95% CI ellipse physiotherapy arm compared with the usual-care arm.
DOI: 10.3310/hta21530 HEALTH TECHNOLOGY ASSESSMENT 2017 VOL. 21 NO. 53
© Queen’s Printer and Controller of HMSO 2017. This work was produced by Thomas et al. under the terms of a commissioning contract issued by the Secretary of State for Health. This issue may be freely reproduced for the purposes of private research and study and extracts (or indeed, the full report) may be included in professional journals provided that suitable acknowledgement is made and the reproduction is not associated with any form of advertising. Applications for commercial reproduction should be addressed to: NIHR Journals Library, National Institute for Health Research, Evaluation, Trials and Studies Coordinating Centre, Alpha House, University of Southampton Science Park, Southampton SO16 7NS, UK.
face-to-face physiotherapy intervention but at lower costs. The probabilities of the interventions being dominant were 85% for the DVD intervention compared with usual care and 51% for the face-to-face physiotherapy intervention compared with usual care. Thus, both the cost-effectiveness analysis and the cost–utility analysis provided congruent results. Both interventions achieved outcome gains at lower total costs than usual care. The lower cost in the DVD group meant that the DVD intervention was preferable to face-to-face physiotherapy. The low cost of the DVD (£2.85) meant that, if effective, it was highly likely to be cost-effective. Further, if made available on the internet, its cost would fall to close to zero.
In conclusion:
l the QALY differences between the treatment arms were in the same direction as the differences in the primary outcome, but were smaller
l the increased cost of each intervention was offset by reductions in total costs so that both interventions dominated usual care
l the DVD/booklet training was preferable to face-to-face physiotherapy, as the outcomes were within the equivalence margin and the DVD intervention had a lower cost.