RT Journal
A1 Reeves WC, Fukuda K, Nisenbaum R, Thompson WW
T1 CHronic multisystem illness among gulf war veterans—reply
JF JAMA
JO JAMA
YR 1999
FD July 28
VO 282
IS 4
SP 327
OP 329
DO 10-1001/pubs.JAMA-ISSN-0098-7484-282-4-jbk0728
UL http://dx.doi.org/10-1001/pubs.JAMA-ISSN-0098-7484-282-4-jbk0728
AB 
First, our study was never intended to replicate or confirm the findings
of Haley et al.1 We are skeptical of his
study findings and conclusions because of substantial study design flaws already
described by others.2- 3
Second, we used a very different approach than Haley et al for choosing symptoms
to study by factor analysis. To prove a hypothesis that neurotoxic exposures
were causing illness among selected Gulf War veterans, Haley et al used unstated
criteria to choose symptoms from reports from various Gulf War registries.
Because we had no preconceived ideas about a Gulf War syndrome, we used open-ended
interviews and examinations of 59 Gulf War veterans and a survey of more than
3700 military personnel from 4 military bases to identify relevant symptoms
for study. This lengthy process provided the most epidemiologically and clinically
sound basis (ie, least open to bias) for identifying important symptoms among
Gulf War veterans. Third, our objective as stated was to study illness in
Gulf War veterans who remained in active service. Fourth, stress is a difficult
factor to measure, because its manifestations and relations to other disorders
are not clear. Although we found only 1 person who met formal criteria for
posttraumatic stress disorder, such criteria are just 1 approach for measuring
stress. A more fundamental observation is that we found multisymptom illness
cases among both Gulf War veterans and, at lower levels, among their nondeployed
peers. It is inescapably logical that important etiologic factors probably
were common to both groups and were not unique to the Gulf War experience;
such factors could include stress. Fifth, we flatly disagree with Haley that
our symptom-based case definition is "incongruous" with our factor analysis
results and is "invalid." The results were highly concordant, and this finding
helped convince us that the factor analysis results were believable. The role
of factor analysis in any study should not be overstated. The meaningfulness
of symptom groupings (ie, factors) identified by factor analysis fundamentally
depends on the symptoms that are selected for study. Claims that factors constitute
disease syndromes should be received with skepticism unless strong supporting
biological or clinical evidence is presented. Sixth, we agree with Haley that
our findings do not necessarily implicate a psychological basis for symptoms
reported by Gulf War veterans. However, unlike Haley, we do not have a particular
etiology to champion. Given the nature of war, it remains probable that psychological
factors have an important contributing role in the development of unexplained
symptoms in some personnel after all wars.4