Free fatty acid supplementation produced small but significant reductions in ADHD symptoms even with probably blinded assessment s , although the clinical significance of these effects remains to be determined .
Artificial food color exclusion produced larger effects but often in individuals selected for food sensitivities .
OBJECTIVE Nonpharmacological treatments are available for attention deficit hyperactivity disorder ( ADHD ) , although their efficacy remains uncertain .
The authors undertook meta-analyses of the efficacy of dietary ( restricted elimination diets , artificial food color exclusions , and free fatty acid supplementation ) and psychological ( cognitive training , neurofeedback , and behavioral interventions ) ADHD treatments .
Searching for unpublished trials in Cochrane reviews may not be worth the effort.
OBJECTIVE To assess the value of search ing for unpublished data by exploring the extent to which Cochrane review s include unpublished data and by evaluating the quality of unpublished trials . STUDY DESIGN AND SETTING We screened all 2,462 completed Cochrane review s published since 2000 in the Cochrane Data base of Systematic Review s Issue 3 , 2006 . In a r and om sample ( n=61 ) of 292 review s , including unpublished trials , we studied all 116 references . RESULTS Unpublished trials make up 8.8 % of all included trials in our sample . Thirty-eight percent of the " unpublished " trials have in fact been published . Allocation concealment was " unclear " or not adequate in 54.3 % and 61.3 % reported blinding . In 47.2 % reported withdrawal rates were > 20 % . Trials that were eventually published had larger mean population sizes ( P-value , 0.02 ) . Of the reported sponsors , 87.3 % were drug companies . Method ological quality and publication bias are mentioned in half of the review s and explored in a third . Quality ratings did not have consequences for pooling , because 82.8 % was included in the forest plots . CONCLUSIONS A minority of Cochrane review s include " unpublished trials " and many of these are eventually published . Truly unpublished studies have poor or unclear method ological quality . Therefore , it may be better to invest in regular updating of review s , rather than in extensive search ing for unpublished data
Free fatty acid supplementation produced small but significant reductions in ADHD symptoms even with probably blinded assessment s , although the clinical significance of these effects remains to be determined .
Artificial food color exclusion produced larger effects but often in individuals selected for food sensitivities .
OBJECTIVE Nonpharmacological treatments are available for attention deficit hyperactivity disorder ( ADHD ) , although their efficacy remains uncertain .
The authors undertook meta-analyses of the efficacy of dietary ( restricted elimination diets , artificial food color exclusions , and free fatty acid supplementation ) and psychological ( cognitive training , neurofeedback , and behavioral interventions ) ADHD treatments .