BackgroundThe preliminary results of a randomised controlled trial are presented. The aim of the trial is to determine the efficacy, feasibility and acceptability of email-delivered psychological interventions with telephone support, for adults injured in a motor vehicle crash engaged in seeking compensation. The primary intention for this preliminary analysis was to investigate those who were psychologically distressed and to stop the trial midway to evaluate whether the safety endpoints were necessary.MethodsThe analysis included 90 adult participants randomised to one of three groups, who were assessed at baseline and post-intervention at 3 months. Cognitive behaviour therapy (CBT) or healthy lifestyle interventions were delivered over 10 weeks, involving fortnightly emailed modules plus clinically focussed telephone support, with the aim of reducing psychological distress. An active waiting list of control subjects received non-clinically focussed telephone contact over the same period along with claim-related reading material. Depression Anxiety Stress Scales (DASS) and Impact of Events Scale (Revised) (IES-R) were used to assess psychological distress. Psychiatric interviews were used to diagnose major depressive disorder and post-traumatic stress disorder. Aspects of acceptability and feasibility were also assessed.ResultsFor those diagnosed with depression at baseline in the CBT group, psychological distress reduced by around 16%. For those with depression in the healthy lifestyle group, distress increased marginally. For those in the control group with depression, distress also decreased (by 18% according to DASS-21 and 1.2% according to IES-R). For those without depression, significant reductions in distress occurred, regardless of group (P < .05). The results suggest that for those with depression, a healthy lifestyle intervention is contraindicated, necessitating the cessation of recruitment to this intervention. The interventions were reported as acceptable by the majority and the data indicated that the study is feasible.ConclusionsCBT with telephone support reduced psychological distress in physically injured people with depression who are engaged in seeking compensation. However, time plus fortnightly telephone contact with claim-related reading material may be sufficient to reduce distress in those who are depressed. For those who were not depressed, time plus telephone support is most likely sufficient enough to assist them to recover. The trial will continue with further recruitment to only the CBT and control groups, over longer follow-up periods.Trial registrationAustralian and New Zealand Clinical Trials Registry: Preventing psychological distress following a motor vehicle accident; ACTRN12615000326594. Registered on 9 April 2015.Electronic supplementary materialThe online version of this article (10.1186/s13063-018-2716-2) contains supplementary material, which is available to authorized users.