Frankly, it looks like your terms were a clear and succinct and accurate
summary of these works. If it devalues the work of others who are doing
good quality work, perhaps this can serve as an impetus for them to get
their work out for us to relish. This is no different than other
"doctor bashing" papers we read: "Docs of Specialty X don't do yyyyy
which has been proven of benefit in the treatment or prevention of
zzzzz." Those docs who are doing yyyyy are either thrown in with the
lot or we learn to be satisfied with the knowledge that we are different
and hope that eventually our colleagues come up to snuff.
Henry C. Barry, MD, MS
Senior Associate Chair
Department of Family Practice Academic Office Phone:
517-353-0851 x 456
B-100 Clinical Center Clinical Office Phone:
Michigan State University Fax:
East Lansing, Michigan 48824-1315 E-mail:
[log in to unmask]
> -----Original Message-----
> From: Simon, Steve, PhD [SMTP:[log in to unmask]]
> Sent: Wednesday, December 16, 1998 9:46 AM
> To: [log in to unmask]
> Subject: Epidemiolofy of RCTs (apology and clarification)
> In a private e-mail, one of the participants of this list suggested
> that my
> comments about
> "Content and quality of 2000 controlled trials in schizophrenia over
> years" Ben Thornley and Clive Adams BMJ 1998; 317: 1181-1184.
> devalued the work of people in this area and that words like
> "terrible" and
> "mess" were needlessly cruel. I'm sorry that my characterization of
> research paper was so extreme. A more accurate description can be
> by quoting from the authors themselves.
> "The quality of reporting was poor. Only 4% (80) of the trials clearly
> described the methods of allocation. Explicit descriptions of blinding
> adequate in only 22% (440) of trials, while some description of
> withdrawals was given in 42% (840)." page 1182.
> "Only 20 trials (1%) raised the issue of the statistical power of the
> The average size of schizophrenia trials was small. For an outcome
> such as
> clinically important improvement in mental state to show a 20%
> between groups a study would have to have 150 participants in each arm
> (alpha=0.05, power 85%). Only 3% (60) of studies were of this size or
> greater. More than 50% of trials had 50 or fewer participants." page
> "In all, 510 (25%) studies did not use rating sclaes to measure
> The remaining 1490 trials used 640 different instruments." and later
> "Overall, 369 scales were used only once." page 1182.
> "The quality of reporting in this large sample of trials was poor and
> no sign of improvement over time. As low quality scores are associated
> an increased estimate of benefit, schizophrenia trials may well have
> consistently overestimated the effects of experimental
> interventions." page
> "Further difficulties with using the evidence generated by this mass
> research are that the studies are of limited duration for an illness
> often lasts decades." page 1183.
> "The findings of this survey are as bad, if not worse, as those for
> disciplines of health care. Certainly, there is a long way to go
> before all
> interventions for patients with schizophrenia have been adequately
> and systematically reviewed and some of the enduring questions about
> efficacy of treatment are answered." page 1183.
> I hope that the direct quotes I have provided give a better sense of
> issues, which, in my opinion, are important for anyone who practices
> Evidence Based Medicine.
> Steve Simon, [log in to unmask], Standard Disclaimer.
> STATS - Steve's Attempt to Teach Statistics: http://www.cmh.edu/stats