Dosage, Intensity, and Frequency of Language Therapy for Aphasia: A Systematic Review–Based, Individual Participant Data Network Meta-Analysis
Authors:   The REhabilitation and recovery of peopLE with Aphasia after StrokE (RELEASE) Collaborators, Brady Marian C. , Ali Myzoon , VandenBerg Kathryn , Williams Linda J. , Williams Louise R. , Abo Masahiro , Becker Frank , Bowen Audrey , Brandenburg Caitlin , Breitenstein Caterina , Bruehl Stefanie , Copland David A. , Cranfill Tamara B. , di Pietro-Bachmann Marie , Enderby Pamela , Fillingham Joanne , Galli Federica Lucia , Gandolfi Marialuisa , Glize Bertrand , Godecke Erin , Hawkins Neil , Hilari Katerina , Hinckley Jacqueline , Horton Simon , Howard David , Jaecks Petra , Jefferies Elizabeth , Jesus Luis M.T. , Kambanaros Maria , Kang Eun Kyoung , Khedr Eman M. , Kong Anthony Pak-Hin , Kukkonen Tarja , Laganaro Marina , Ralph Matthew A. Lambon , Laska Ann Charlotte , Leemann Béatrice , Leff Alexander P. , Lima Roxele R. , Lorenz Antje , MacWhinney Brian , Marshall Rebecca Shisler , Mattioli Flavia , Maviş İlknur , Meinzer Marcus , Nilipour Reza , Noé Enrique , Paik Nam-Jong , Palmer Rebecca , Papathanasiou Ilias , Patricio Brigida , Martins Isabel Pavão , Price Cathy , Jakovac Tatjana Prizl , Rochon Elizabeth , Rose Miranda L. , Rosso Charlotte , Rubi-Fessen Ilona , Ruiter Marina B. , Snell Claerwen , Stahl Benjamin , Szaflarski Jerzy P. , Thomas Shirley A. , van de Sandt-Koenderman Mieke , van der Meulen Ineke , Visch-Brink Evy , Worrall Linda , Wright Heather Harris 
Published: December 2021

Background and Purpose:
Optimizing speech and language therapy (SLT) regimens for maximal aphasia recovery is a clinical research priority. We examined associations between SLT intensity (hours/week), dosage (total hours), frequency (days/week), duration (weeks), delivery (face to face, computer supported, individual tailoring, and home practice), content, and language outcomes for people with aphasia.

Methods:
Databases including MEDLINE and Embase were searched (inception to September 2015). Published, unpublished, and emerging trials including SLT and ≥10 individual participant data on aphasia, language outcomes, and time post-onset were selected. Patient-level data on stroke, language, SLT, and trial risk of bias were independently extracted. Outcome measurement scores were standardized. A statistical inferencing, one-stage, random effects, network meta-analysis approach filtered individual participant data into an optimal model examining SLT regimen for overall language, auditory comprehension, naming, and functional communication pre-post intervention gains, adjusting for a priori–defined covariates (age, sex, time poststroke, and baseline aphasia severity), reporting estimates of mean change scores (95% CI).

Results:
Data from 959 individual participant data (25 trials) were included. Greatest gains in overall language and comprehension were associated with >20 to 50 hours SLT dosage (18.37 [10.58–26.16] Western Aphasia Battery–Aphasia Quotient; 5.23 [1.51–8.95] Aachen Aphasia Test–Token Test). Greatest clinical overall language, functional communication, and comprehension gains were associated with 2 to 4 and 9+ SLT hours/week. Greatest clinical gains were associated with frequent SLT for overall language, functional communication (3–5+ days/week), and comprehension (4–5 days/week). Evidence of comprehension gains was absent for SLT ≤20 hours, <3 hours/week, and ≤3 days/week. Mixed receptive-expressive therapy, functionally tailored, with prescribed home practice was associated with the greatest overall gains. Relative variance was <30%. Risk of trial bias was low to moderate; low for meta-biases.

Conclusions:
Greatest language recovery was associated with frequent, functionally tailored, receptive-expressive SLT, with prescribed home practice at a greater intensity and duration than reports of usual clinical services internationally. These exploratory findings suggest critical therapeutic ranges, informing hypothesis-testing trials and tailoring of clinical services.

Registration:

URL:
https://www.crd.york.ac.uk/PROSPERO/
; Unique identifier: CRD42018110947.