Abstract
Objective
Our objective was to evaluate the long-term impact of n-of-1 trials—within-patient randomised, double-blind, cross-over comparisons of stimulant versus placebo or stimulant—on ADHD management.
Methods
Telephone surveys at 3, 6 and 12 months. Main outcome measures included (1) changes in treatment before and after the n-of-1 trial, (2) congruence of management at follow-up with trial result, (3) reasons for any non-congruence, and (4) persistence of the joint patient-doctor decision over 12 months. Patients were children with clinically diagnosed ADHD, aged 5–16 years.
Results
A total of 76 patients were followed up; 12 months’ data were available for 67 (88%). Management changed from baseline for 46, 48 and 51% at 3, 6 and 12 months respectively. Most responders, 21/37 (57%), remained on the same stimulant at 12 months, compared to 9/24 (37%) non-responders. Of the remaining non-responders, 15/24 (62%) either switched (2/24, 8%) or ceased stimulants (13/24, 54%). The rate of congruence with the test result was 45/65 (69%) at 3 months, 44/67 (66%) at 6 months and 40/67 (60%) at 12 months. Persistence with the post-trial decision over 12 months was high (79–85%) whether the decision was to continue or to cease stimulants.
Conclusions
Although not conclusive because there was no control group, our results suggest that n-of-1 trials may improve rational treatment of ADHD.
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Acknowledgements
Thanks to the General Practice Evaluation Program, the Department of Health and Aged Care, Queensland Medical Laboratory (QML) and the Royal Australian College of General Practitioners for funding; QML and Mater Misericordiae Health Services, Brisbane, for delivering the service; Paul Glasziou for the initial concept; Cate Duggan, Tina Janamian, Peter Coxeter, Kate Del Mar, Sharyn Herzig, Julie King, Jacob Carter, Donna-Marie Preston, Robyn Brown, Brenda Rosser, and Grace McBride for research assistance; and the participants. Jane Nikles held a National Health and Medical Research Council Scholarship 210364.
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Nikles, C.J., Mitchell, G.K., Del Mar, C.B. et al. Long-term changes in management following n-of-1 trials of stimulants in attention-deficit/hyperactivity disorder. Eur J Clin Pharmacol 63, 985–989 (2007). https://doi.org/10.1007/s00228-007-0361-x
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DOI: https://doi.org/10.1007/s00228-007-0361-x