Recombinant growth hormone (GH) is used to treat short stature in children with GH deficiency and other conditions. Treatment adherence, which may be poor because of the need for daily injections and treatment length, may be improved with easy-to-use injection devices.
The aim of this study was to compare patient preference and use errors of a new GH injection pen (Norditropin FlexPro; Novo Nordisk A/S, Denmark) relative to four other pens: easypod (Serono, Switzerland), Genotropin pen (Pfizer, USA), Nutropin AQ NuSpin pen (Genentech, USA), and Omnitrope pen (Sandoz, Germany).
In two noninterventional, randomized, crossover studies, children (10–17 years) treated with GH (≥6 months) were randomly assigned to intuitiveness (n = 30, n = 32) or instruction (n = 26, n = 32) groups. All subjects performed a usability test involving needle attachment, dose setting, and injection into an Eppendorf tube. Intuitiveness groups had brief verbal instructions on device use. Instructed groups were instructed in full according to the user guide. Patient preference for devices was assessed by a 13-item questionnaire. The number and type of use errors were recorded.
FlexPro was rated as the most preferred device in the majority of items in intuitiveness (9/13, 11/13) and instructed groups (10/13, 11/13) and was the most preferred device in both groups (intuitiveness: 15/30, 19/32; instruction: 19/26, 23/32). FlexPro scored highest for ease of use, easypod for best delivery feedback, Genotropin and NuSpin pens for appearance and quality. Technical errors were less with FlexPro (1 to 2 errors) than with comparator devices (9 to 39 errors) in intuitiveness groups, and fewer errors were recorded in instruction groups (1 to 2 errors for each device).
Both instructed and uninstructed patients preferred Norditropin FlexPro to comparator devices. The numbers of errors in the intuitiveness group reflect the problems/errors patients or caregivers face when they have not received training or do not understand it. Overall, use of FlexPro was associated with fewer errors than the comparator devices.
An easy and less error-prone device may help improve treatment adherence. Training can reduce error rate.
© 2012 Published by Elsevier Inc.