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. 2023 Mar 27;2023(3):CD009885. doi: 10.1002/14651858.CD009885.pub3

Tannock 2018.

Study characteristics
Methods A 10‐week to 4 months parallel‐trial with 2 arms, which were further parted into 3 trial arms of different reading therapy:
  • IR‐MPH

  • placebo


Phases: 2 phases (open‐label titration and double‐blind intervention)
Participants Number of participants screened: 221
Number of participants included: 65 (49 boys, 16 girls)
Number of participants followed‐up: 49 (15 teacher ratings and 1 parent rating not completed)
Number of withdrawals: 16 (15 teacher ratings and 1 parent rating not completed)
13 participants changed their allocated intervention (8 from MPH group, 5 from placebo group)
Diagnosis of ADHD: DSM‐IV (subtype not stated)
Age: mean 8.5 years (SD 1.4, range 7‐11)
IQ: 91.5 (SD 10.6)
MPH‐naive: not stated
Ethnicity: white (90%), African‐American (4%), Hispanic (1%), and Asian (5%)
Country: Canada
Setting: classroom laboratory in a clinical setting
Comorbidity: all participants had a reading disorder. 29.3% had ODD 8.6% had CD
Comedication: not stated
Additional sociodemographics: socioeconomic status: 6.4 (SD 1.7)
Inclusion criteria
  • DSM‐IV diagnosis of ADHD and Reading Disorder (based on a clinical diagnostic assessment)

  • Aged between 7 and 11 years old

  • IQ > 80 (confirmed with WISC‐III)

  • A diagnosis of RD based on low achievement criteria, namely, a score of at least 1.5 standard deviations below age‐level expectations on at least 2 of the standardised reading tests, or 1 standard deviation below age‐level expectation on 3 tests

  • Full‐time attendance in a local school and consent for the child to be withdrawn from class to participate in the intervention trial

  • English as the primary language spoken by parent and child

  • Parental consent for the child to participate in the randomised controlled trial


Exclusion criteria
  • Receiving pharmacological treatment for ADHD at the start of the trial

  • Children attending full‐time French immersion programmes

  • Chronic medical or neurological conditions or history of head injury/loss of consciousness requiring hospitalisation

  • Children with a history of adverse or poor response to stimulant medication

Interventions Participants were randomly assigned to receive either MPH at optimal dosage or placebo twice/d, while also receiving one of 3 reading interventions.
Number randomised to each group: 39 to MPH, 26 to placebo. 13 participants changed their allocated intervention (8 from MPH group, 5 from placebo group)
Mean medication dosage: not stated. Maximum oral dose of 0.7 mg/kg twice/d or 20 mg twice/d
Administration schedule: twice/d, in the morning and before lunch
Duration of each medication: 12‐13 weeks or 4‐5 months of MPH or placebo
Washout before trial initiation: no information
Titration period: 2‐3 week titration phase in which the dose of MPH or placebo was increased in 5 mg steps. Identical, scored, 10 mg pills of MPH and placebo were used
Treatment compliance: research staff recorded the number of pills returned at trial completion (average of about 90%).
Outcomes ADHD symptoms
  • Parent and teacher versions of the CRS‐R


Serious AEs
  • None stated


General behaviour
  • Oppositional Behavior subscale of the parent and teacher CRS‐R

  • IOWA‐CRS (during blinded titration phase ‐ results are not available and therefore not included in our analysis)


Non‐serious AEs
  • Side Effect Rating Scale (during blinded titration phase ‐ results are not available and therefore not included in our analysis)

Notes Sample calculation: no
Ethics approval: no
Comments from trial authors
  • "The main limitations of our study included the small sample sizes and attrition from the assigned medication condition prior to commencing the academic programs both of which threaten the study’s internal validity."


Key conclusion of trial authors
  • "Active medication treatment, while improving the behavioral symptoms of ADHD, does not result in gains in reading ability in this comorbid group of children in the absence of concurrent reading remediation treatment."


Comments from review authors
  • Review authors are uncertain if trial duration (besides titration period) is 4 months (amount of pills given to parents) or 10 weeks (length of reading intervention).


Exclusion of MPH non‐responders/children who have previously experienced AEs while taking MPH: yes
Any withdrawals due to AEs: not stated
Funding source: an operating grant from the Canadian Institutes of Health Research (Grant #MT 13366), and by the donation of placebo medication from Novartis Pharmaceuticals.
Email correspondence with the trial authors: September 2021. We sought supplemental information regarding details of the medical intervention through personal email correspondence with the authors in September 2021. Unfortunately the data are no longer available.
Risk of bias
Bias Authors' judgement Support for judgement
Random sequence generation (selection bias) High risk 20% of parents (n = 13) requested a change in their child’s assigned medication condition (8 from placebo to MPH; 5 from MPH to placebo)
Allocation concealment (selection bias) Low risk Parents were then provided with a 4‐month supply of pills, each month packaged separately.
Blinding of participants and personnel (performance bias)
All outcomes Low risk "The MPH and placebo pills were identical in color, shape and size and were administered in a double‐blind manner twice daily (once in the morning before school and once at lunch)"
Comment: 1 participant was unblinded during requested change of medication assignment
Blinding of outcome assessment (detection bias)
All outcomes Low risk "We analysed behavioral data when both parent and teacher reports were present to ensure that results from these 2 sources could be compared"
Incomplete outcome data (attrition bias)
All outcomes High risk "Within the initial 2‐week dose‐adjustment phase and prior to starting the academic programs, 20% of parents (n= 13) requested a change in their child’s assigned medication condition (8 from placebo to MPH; 5 from MPH to placebo)."
Comment: an ITT analysis as well as an as‐treated analysis was made
Selection bias (e.g. titration after randomisation → exclusion of MPH non‐responders or placebo responders): there was a titration phase after randomisation
Selective reporting (reporting bias) Unclear risk No trial protocol identified