**5. Strengths and limitations**

To reflect the impact of PTSD symptoms on daily life, the presented studies were characterized by a broad approach to the subject of treating trauma-related disorders in later life. Consequently, PTSD, comorbid depression and several measures of resilience were included in the analyses. An additional strength is the multimethod approach of this research project. The studies used advanced and variable methods of analysis. A third strength is the controlled comparison of treatment response in two innovative psychotherapeutic interventions for PTSD in a sample of older adults. The interventions had contrasting treatment approaches: imaginal exposure (focusing on the past) versus a focus on problem-solving in the present. The resulting response patterns may provide a useful tool for clinicians to discuss treatment preferences with their patients. The equal efficacy at follow-up might be an important attribution to ongoing discussions concerning the necessity of exposure in trauma treatment [46]. The clinical meaningfulness of the results was increased by the inclusion of a heterogeneous sample of civilians, including both native Dutch civilians and refugees. In addition, the participants were allowed to determine session intervals in accordance with their preferences and possibilities. Advanced statistical analyses addressed the resulting variability of inter-assessment intervals. Within a clinical environment, methodological rigor was addressed by randomization, protocol adherence, checks of treatment adherence and interrater reliability, and the use of independent assessors.

Some limitations merit attention as well. The participants' mean age does not allow for generalizing the research findings to old age (over age 74). By using the 55 years

*Treating Trauma-related Disorders in Later Life: Moving Forward DOI: http://dx.doi.org/10.5772/intechopen.102499*

limit, however, clinically important transitions could be captured and enough participants could be recruited to reach a sufficiently powered sample for the RCT on PTSD. Nevertheless, the study sample was small and mainly representative for the socalled young-old (ages 55 to 75), as distinguished [47] from the old-old (75 and over). In addition, out of fear of high dropout and concurrent influences in the follow-up interval, a short follow-up interval was chosen. In future research, a longer follow-up interval is strongly advisable. Therefore, the research findings from these studies have to be interpreted with caution. They can contribute, however, to ongoing discussions in the field of treating trauma-related disorders in later life, focusing on current issues and controversies, lessons learnt and future research. These topics will receive more attention in the following paragraphs.
