Medicine, Health Care and Philosophy

, Volume 21, Issue 3, pp 335–345 | Cite as

Patient-specific devices and population-level evidence: evaluating therapeutic interventions with inherent variation

  • Mary Jean WalkerEmail author
Scientific Contribution


Designing and manufacturing medical devices for specific patients is becoming increasingly feasible with developments in 3D printing and 3D imaging software. This raises the question of how patient-specific devices can be evaluated, since our ‘gold standard’ method for evaluation, the randomised controlled trial (RCT), requires that an intervention is standardised across a number of individuals in an experimental group. I distinguish several senses of patient-specific device, and focus the discussion on understanding the problem of variations between instances of an intervention for RCT evaluation. I argue that, despite initial appearances, it is theoretically possible to use RCTs to evaluate some patient-specific medical devices. However, the argument reveals significant difficulties for ensuring the validity of such trials, with implications for how we should think about methods of evidence gathering and regulatory approaches for these technologies.


Medical device Regulation Randomised controlled trial Personalised medicine 3D printing 



My thanks to Robert Sparrow, Wendy Rogers, David Wotton, Tajanka Mladenovska, and the anonymous referees for this journal, for their comments on previous drafts. The funding was provided by Australian Research Council (Grant No. CE140100012)


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Copyright information

© Springer Science+Business Media B.V. 2017

Authors and Affiliations

  1. 1.Ethics Program, ARC Centre of Excellence for Electromaterials ScienceMonash UniversityClaytonAustralia
  2. 2.Philosophy Department, School of Philosophical, Historical and International StudiesMonash UniversityClaytonAustralia

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