A systematic review and economic model of the effectiveness and ...

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Clinical effectiveness
Results of the MTA trial
The MTA trial was designed to answer three
questions: 76
1. Do medication and behavioural treatments result in
comparable levels of improvement in pertinent
outcomes at the end of treatment?
Medication management was superior to
behavioural treatment for three (of five)
measures of ADHD core symptoms. No
significant differences were observed across the
other key dimensions.
2. Do participants assigned to combined treatment show
higher levels of improvement in overall functioning
in pertinent outcome domains than those assigned to
either medication management or behavioural
treatment at the end of treatment (one-tailed
hypotheses)?
(a) Combined treatment and medication
management do not differ significantly
across any domain.
(b) Combined treatment was superior to
behavioural management on three (of five)
measures of ADHD core symptoms, for one
(of three) measures of
aggression/oppositional behaviour, for one
(of three) measure of anxiety depression
and for one (of three) measure of academic
achievement. No significant differences
were observed in social skills or
parent–child relations.
3. Do participants assigned to each of the three MTA
treatments (medication management, behavioural
treatment and combined treatment) show greater
improvement over 14 months than those assigned to
community care (one-tailed)?
(a) Medication management was superior to
community care for three (of five) measures
of ADHD symptoms, for two (of three)
measures of aggression/oppositional
behaviour and for one (of two) measures of
social skills. No significant differences were
observed in anxiety/depression or
parent–child relations.
(b) No significant differences between
behavioural management and community
care were observed for any outcome
domains.
(c) Combined treatment was superior to
community care for four (of five) measures
of ADHD symptoms, for two (of three)
measures of aggression/oppositional
behaviour, for one (of three) measures of
anxiety/depression, for both measures of
social skills, for one (of two) measures of
parent–child relations and for one (of three)
measures of academic achievement.
The MTA Cooperative Group conducted further
analysis to identify patient subgroups with better
or worse response to the various treatment
strategies. 105 This analysis should be seen as
exploratory, because of the danger of repeated
statistical testing with a sample not designed for
this purpose. There was no difference in treatment
response by sex, prior treatment or presence of comorbid
disruptive disorders. Behavioural
treatment appeared to be more effective in
children with anxiety disorders and children from
deprived backgrounds.
Since the publication of the previous NICE
report, 4 the authors of the MTA trial have
published a number of related papers. 106–113 Most
of these are cross-sectional analyses, overview
studies or studies focusing on covariates, such as
socio-economic status or ethnicity, which will not
be discussed in this report. 106,107,110,111
Other papers focused on subgroup
analyses. 108,109,112 As the samples were not designed
for this purpose, results should be interpreted with
caution. Vitiello and colleagues examined the
trajectory of MPH dosage over time, following a
controlled titration. 108 The aim was to ascertain
how accurately the titration was able to predict
effective long-term treatment in children with
ADHD. They concluded that for most children,
initial titration found a dose of MPH in the general
range of the effective maintenance dose, but did
not prevent the need for subsequent maintenance
adjustments. 108 Greenhill and colleagues 109
examined whether the trial identified the best MPH
dose for each child with ADHD. They found that
the MTA titration protocol validated the efficacy of
weekend MPH dosing and established a total daily
dose limit of 35 mg of MPH for children weighing