Posttraumatic stress disorder

Posttraumatic stress disorder

Posttraumatic stress disorder (PTSD) become familiar into the world

psychiatric nomenclature in 1978 (World Health Organization, 1978) with

the issuance of the ICD-9, documenting the cross-cultural recognition

of the typical symptomatic response to exposure to traumatic life events

[1, 2] The characteristic core of the disorder includes the

the distressing oscillation between intrusion and avoidance. Intrusion is

characterized by nightmares, unbidden visual images of the trauma or its

aftermath while awake, intrusive thoughts about aspects of the traumatic

event, sequelae, or self-conceptions. Avoidance is typified by deliberate efforts to not think about the event, not talk about the event, and avoiding reminders of the event. Also characteristic are more active attempts to

push memories and recollections of the event or its aftermath out of mind

by increasing the use of alcohol or drugs, overworking, or other strategies

designed to divert attention or to so exhaust someone that he or she is

temporarily untouched by the intrusive phenomenology. In addition to

the frank avoidance, Horowitz also described emotional numbing as a not

uncommon sequel to exposure to a traumatic life event[2, 3]

Despite the usefulness of the original IES, complete assessment of the

response to traumatic events required tracking of response in the domain

of hyperarousal symptoms. Beginning with data from a longitudinal

study of the response of emergency services personnel to traumatic

events, including the Loma Prieta earthquake ( Weiss, Marmar,

Metzler, & Ronfeldt, 1995)[4], a set of seven additional items, with six to tap

the domain of hyperarousal, and one to parallel the DSM-III-R and now

DSM-IV diagnostic criteria for PTSD were developed, piloted, and then

used. These additional seven items were interspersed with the existing

seven intrusion and eight avoidance items of the original IES using a table

of random numbers to establish placement. The IES-R comprises these 22

items, and was originally presented in the first edition of this reference

work (Weiss & Marmar, 1997). [5]

An important consideration in the construction of the revised IES

was to maintain comparability with the original version of the measure as

much as was possible. Consequently, the one-week time frame to which

the instructions refer in measuring symptomatic response was retained,

as was the original scoring scheme of frequency – 0, 1, 3, and 5 for the

responses of “Not at all,” “Rarely,” “Sometimes,” and “Often.” The only

modification to the original items that were made was to change the item

“I had trouble falling asleep or staying asleep” from its double-barreled

status into two separate items. The first is simply “I had trouble staying

asleep” and because of a somewhat higher correlation between it and the

remaining intrusion items it was assigned to represent the original item

in the Intrusion subscale. The second item, “I had trouble falling asleep”

was assigned to the new Hyperarousal subscale because of its somewhat

higher correlation with the other hyperarousal items, it is somewhat lower

correlation with the intrusion items, and its more apparent link with

hyperarousal than with intrusion. The six new items comprising the

Hyperarousal subscale target the following domains: anger and irritability,

jumpiness and exaggerated startle response, trouble concentrating, psychophysiological

arousal upon exposure to reminders, and hypervigilance. As

mentioned earlier, the one new intrusion item taps the dissociative-like

reexperiencing captured in true flashback-like experiences. The reader is

referred to Weiss (2004) [6] for a summary of the internal consistency of the

three subscales, all of which were strong, the pattern of item-total correlations,

test-retest stability, which was also satisfactory, and commonality of

the interitem correlations.

Based on the experience with those data, and considerations of

the insufficiency of frequency as a completely summarizing marker for

self-report, the over-weighting of responses of “Sometimes” and “Often”

in the scoring scheme, the IES-R moulted into a measure with the following

characteristics: (1) the directions were modified so that the respondent

is not asked about the frequency of symptoms in the past 7 days but is

instead asked to report the degree of distress of the symptom in the past

7 days; (2) the response format was modified to a 0–4 response format with

equal intervals − 0 = Not at all, 1 = A little bit, 2 = Moderately, 3 = Quite a

bit, 4 = Extremely – rather than the unequal intervals of the original scale;

and (3) the subscale scoring was changed from the sum of the responses

to the mean of the responses, allowing the user to immediately identify

the degree of symptomatology merely by examining the subscale scores,

since they are presented in the same metric as the item responses,

something the original scale did not. According to Derogatis, (1994), [7] these changes brought the IES-R in parallel format to the SCL-90-R () allowing for direct comparison

of endorsement of symptom levels across these two instruments.

For a variety of reasons, many measures that have

contributed to the growing cross-cultural literature in traumatic stress

and PTSD were initially developed in English. The IES-R being no exception.

Consequently, for use with samples whose native language is not

English, a translation of the measure is required. Given this requirement,

it is useful to review some of the issues involved in that process.

Mallinckrodt and Wang (2004) [8] borrowed from Hambleton’s work on

the difference between literal translation and what is described as the adaptation

of items from one language to another. For example, the English

phrase “go on automatic pilot” if translated literally into German, will not

give the sense of engaging in behaviours without active deliberation that is

only recognized after the fact. Thus, if only a literal translation were

adopted, the reliability and validity would be compromised. Mallinckrodt

and Wang (p. 369) present Hulin’s view that “[a] pair of items from the

original scale and its adapted version are said to be equivalent when two

individuals with the same amount or level of the construct being measured

have equal probabilities of making the same response to the different

language versions of the same item.”

Flaherty et al. (1988) [9] suggested that there were five levels of equivalence

that an adapted measure should possess to show that it has

cross-cultural validity. The first, content equivalence, involves establishing

that the content domain of items is relevant and appropriate for both cultures.

The second, they describe as semantic equivalence, establishing that

each item of the new measure communicates the meaning of its parallel

item on the original scale. The third is more methodological: technical

equivalence addresses the question of whether the data collection method

(e.g., self-report) produces comparable results in each culture. The fourth,

criterion equivalence, involves evidence of parallel comparisons to within cultural

norms. The fifth and final equivalence is conceptual. This addresses

whether the intended construct or phenomenon has the same meaning in each

culture. The claim of ordered equivalence posits that subsequent levels

of equivalence cannot be achieved in the absence of equivalence in all

prior levels.

The efficiency and directness of the IES-R have led scholars in a variety of

different countries and cultures to produce versions in non-English languages.

A review of the literature revealed that the work accomplished for

the international versions approached the recommendations of

Mallinckrodt and Wang (2004)[8] to varying degrees. It is, of course, an

empirical question as to whether the detailed and extensive approach

suggested by these authors would produce a more reliable or valid version

than a more manageable approach. Published data are in the literature

for formal translations as well as ad hoc translations in the context of

an investigation of another question. Of the former, the following versions

can be found (listed alphabetically): Chinese (Wu & Chan, 2003),[10] French

(Brunet, St-Hilaire, Jehel, & King, 2003)[11], German (Maercker & Schuetzwohl,

1998),[12] Japanese (Asukai et al., 2002),[13] and Spanish (Baguena et al., 2001)[14].

A Bosnian version of the IES-R is described in a study that compares

refugees to nonrefugee (Hunt & Gakenyi, 2005).[15] and there is no validated Arabic version which follows Mallinckrodt and Wang protocol[8] and as there is need to assess the impact of different events on our society which compatible without language and culture to raise the bar of scale accuracy when used in our community