If I get your question right, I think you need a control group for comparison. I don't think any pre-intervention information would solve the problem of distinguishing the effect of intervention from the "natural course" of the case with no intervention.

If it is considered unethical to provide no intervention in the control group, you need to compare the intervention results with the development in a control group receiving "treatment as usual" (TAU) - whatever that is in the context of the study.

There are quite some literature on short debriefing interventions, and a meta-analysis showing that the effect tend to be negative. BPR Gersons made a recommendable comment after the publishing of the NICE guidelines in this field: 

BMJ. 2005 May 7; 330(7499): 1038–1039. doi: 10.1136/bmj.330.7499.1038

PMCID: PMC557213 Coping with the aftermath of trauma. NICE recommends psychological therapy for post-traumatic stress disorder. Berthold P R Gersons, professor of psychiatry.

(1. National Institute for Clinical Excellence. The management of post traumatic stress disorder in primary and secondary care. London: NICE, 2005.

2. Rose S, Bisson J, Wessely S. Psychological debriefing for preventing post traumatic stress disorder (post traumatic stress disorder). Cochrane Database Syst Rev 2002. Issue 2: CD000560. [PubMed]

3. Gist R, Devilly GJ, Post-trauma debriefing: the road too frequently travelled. Lancet 2002;360: 741-2. [PubMed]

4. van Emmerik AA, Kamphuis JH, Hulsbosch AM, Emmelkamp PM. Single session debriefing after psychological trauma: a meta-analysis. Lancet 2002;360: 766-71. [PubMed])

I am not updated on more recent research on this.

So, as there seems to be a risk of doing harm with a well-intended intervention, you need to read the literature thoroughly and prefereably consult with experienced researchers in the field, before starting a new project.

Literature on Randomised Controlled Trials will also be useful. 

Thanks Martin! I am familiar with the the Rose & Girst publications but not the others... but I probably wasn't clear.... A current example - the Airport and Train explosions in Brussels.... if someone were to provide some form of PFA to folks who experienced that trauma... there wouldn't be a way to have a Pre-Event Measure to compare Post intervention outcome... and in this situation there is not really a natural Control Group.... sorry to be somewhat circuitous... but that is the nature of the beast in attempting to measure any Crisis intervention... And yes aware of debate of Do No Harm and the history of how that concern developed post 9/11..... In the US the emphasis these days is to take a resiliency approach.... but no one has been able to create a valid & reliable measurement tool to provide authentic outcome results.....and that is why trying to find pointer in the literature that might facilitate the design of such a tool...

Dear Patricia

This is a true dilemma - but not much different from reserch on new "pills". When we believe some treatment works, we want to give it to everybody who need it. But If we want to know if it works, we need to compare the effect with somebody who dont get the treatment - or compare usual treatment with new treatment. So we need to leave part of the group without the treatment we believe is the best. At least for some time (waiting-list control design)

It would of course be wise to collect relevant info on pre-trauma history, but I don't think it can solve the problem. 

In the literature on work stress and depression, questions are asked on family disposition and previous episodes, and adjustments are made for demographic and socio-economic variables.

Thanks Martin... yes a true dilemma especially for a clinician..... who is also a researcher...

Excactly :)

Hi Patricia,

We deal with this issue in rehabilitation quite frequently (depending on the question) because there isn't often good pre-morbid information available. Emergency medicine deals with this issue also. I think that Martin is right that this is probably best solved as a design issue (i.e., find the best natural comparison "control" group that you can).  In rehab we often ask the person to reflect back and self-report what their status was like prior to the onset of illness or injury, although that has it own set of limitations.

Hi Trudy,  Yes, I had heard that the rehabilitation field has to deal with this same issue - do you have any references for me to scan, to see how they describe their design..... Yes, am aware can ask client/patient to reflect backwards..... just a little trickier if have never been in a terrorist situation... and how to compare backwards from that.... but you just gave me an idea that perhaps the PTSD world might have some literature on this.... Thanks for your comment!

:) You know I nearly mentioned the PTSD literature to you as I think it also deals with this issue. I'm not sure I'm aware of any study that would fit your situation exactly but this one popped up on PubMed and it seems pretty typical in terms of how I have seen this handled in rehab settings.  http://dx.doi.org/10.1017/S1041610215002306 

Thanks a million!

I would like to point out that the pre-intervention state is not necessarily a proper control since the intervention is usually only applied to persons happening to need an intervention opposed to a general population. The most common design in this case is keep track of the intervention over time. From an evaluation perspective there are a number of aspects of the intervention to keep track of: activities and time spend with the client, intermediate progress made with the client etc. If EMDR is part of the intervention there are also measures such as SUD scores to include in the client reports.

So unless your intervention consists of a single contact there is nearly always an opportunity to include time related records that can be used to establish an evaluation of the results obtained.

Design is not something one can just copy from a standard textbook example but it requires creativity and problem solving on the part of the researcher. Success!

Rudo

Hi Rudo,

That is exactly the challenge with most CIR interventions, it is a one time intervention.... so difficult to create several data points. BTW - What exactly do the terms EMDR and SUD refer to.... not familiar with these anachronisms.... Thanks!

Hi Patricia, these terms stem from psychotherapy: EMDR is one of the methods used during PTSD ttreatment . As part of the treatment SUD scores are collected that provide an indication of the severity of images for the patient. These are collected during the standard execution of the treatment protocol.

I can see what your problem is with CIR interventions. Nevertheless I am sure the interventions include decision making by intervening team and therefore do include data collection on which such decisions are based. While such information does not completely replace pre-event information, it does include pre-intervention information and I hope that type of information could serve as a evaluation starting point....

Thanks Rudo for the clarification of EMDR & SUD.... and yes, usually a workplace has some statistics on their workforce that might be used as a type of pre-measure after a CIR event.... but just checking to see if someone has come up with a unique way of collecting that information..... Thanks!