SO CARELESSS OF THE SINGLE TRIAL
Tennyson's wry comment on Darwinian natural selection ‘so careful of the type she seems, so careless of the single life’, now seems to have extended to the single trial. Systematic reviews now provide the evidence base, and as these include data from many trials they can be combined cleverly, and almost painlessly, to give a collective summary of the value of any specific intervention. In this context, single trials, although given proper acknowledgement in tables and references, as in Furukawa et al's () comprehensive review, are now largely off-stage unless individual studies are very large. This is unfair, as without the trials there could be no review of worth, as all trials, and even systematic reviews, can change their conclusions radically as more data from new trials are collected (Reference Evans, Evans and MorganEvans et al, 2005; Reference Linde, Berner and EggerLinde et al, 2005). But it does no harm to concentrate on individual ones too, particularly as trials are becoming more complex and the sum total of the effects can include many potential interactions as well as the ostensible measured ones (Reference Campbell, Fitzpatrick and HainesCampbell et al, 2000). Although complexity is deemed to be greater for psychological interventions in psychiatry, drug treatments are not exempt; so, for example, in the trial of Perahia et al () there can be many interpretations of the data presented in Figure 3 that say a great deal about the drug being investigated. Howard & Thornicroft () show that patient power now extends to trials too and complicates matters still more.
We publish the largest controlled trial of cognitive–behavioural therapy in bipolar disorder, supported by the Medical Research Council, in this issue (Scott et al, ), together with a commentary (Lam, ). These are worth a careful read. It is too easy to merely look for summaries, odds ratios and effect sizes when trying to find out what is happening in trials, but the text needs thoughtful examination too. Austin Bradford Hill, the originator of the randomised controlled trial, always emphasised that such a trial answered a ‘precisely framed question’ and one of the problems with systematic reviews is that they answer common questions rather than precisely framed ones. Scott et al ask whether cognitive–behavioural therapy prevents relapse in those ‘who had experienced at least one recurrence of bipolar disorder in the preceding year’ (p. 313). This included one in three who were in an acute episode when recruited. Their results led to a negative answer to their question. Lam et al (Reference Lam, Watkins and Hayward2003) recruited patients only after an episode had occurred and so their question was subtly different: ‘does cognitive–behavioural therapy prevent relapse in those who are in remission from bipolar disorder?’ Their answer was positive. So how do we interpret these contradictory findings? The answer is far from easy and we will be publishing a rejoinder to Lam from Scott et al in our next issue. Does cognitive–behavioural therapy have an important place in the management of bipolar disorder? According to Bradford Hill, you the reader, and especially you the clinician, should have the last word:
‘When does a heap really become a heap? The answer, I submit, is not to be found tidily tucked up in the formulae of tests of significance, useful as they may be. In it there must always be an element of the subjective – the subjective judgment of the particular respondent, of you and me’ (Reference HillHill, 1962: p. 188).
ONLINE CPD
This month the Royal College of Psychiatrists is launching a CPD Online training resource. Details are to be found on the website (http://www.rcpsych.ac.uk/cpd). Although we have had the framework of this project organised for some time we now have some educational modules available for training. ‘Continuing professional development’ is the right phrase for all engaged in this venture; we need help in developing this facility to its potential and look forward to regular feedback from our members to decide whether our efforts are perceived as useful, friendly and relevant to need. We have a long way to go, but we hope this will prove to be a significant step forward in a global educational initiative.
PUBLICATION SCORN OR ENVY
Some of the most wounded correspondents whose work has been rejected by the Journal in recent months are as much upset by the authors we do publish as by the rejections they themselves receive. Their views could be represented (with apologies to our female readers, who I have to admit are not quite as prickly here):
‘Why publish him rather than me?
I have much higher pedigree
My papers excite, are on everyone's lips
His can be used only for wrapping round chips
My views are well-rounded, creative and wise
Whilst his are all muddled with fancy surmise
Now change your mind as I'm sure you'll agree
Why on earth publish him rather than me?’
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