Participants first received Sound Production Treatment - Blocked (SPT-B) for 20 treatment sessions spanning approximately 7 weeks. After a washout period of 2 weeks, they then received Sound Production Treatment - Random (SPT-R) for 20 treatment sessions. Follow-up measures were conducted at 2, 6, and 10 weeks following the end of all treatment.

Participants first received Sound Production Treatment - Random (SPT-R) for 20 treatment sessions spanning approximately 7 weeks. After a washout period of 2 weeks, they then received Sound Production Treatment - Blocked (SPT-B) for 20 treatment sessions. Follow-up measures were conducted at 2, 6, and 10 weeks following the end of all treatment.

Sound Production Treatment is a treatment for acquired apraxia of speech. Combines therapist modeling, simultaneous production, articulatory instruction, feedback and repeated practice. SPT-Blocked entailed practicing all treatment targets blocked by target. SPT-Random entailed practicing all treatment targets in a non predictable, random order.

Change in accuracy of articulation of trained items as measured from baseline to 10 weeks post treatment using effect size calculations as the indicator of magnitude of change; production of words designated for treatment was measured repeatedly in non treatment probes prior to treatment, throughout all study phases, and at 10 weeks post treatment with percent accuracy calculated for each probe (maximum = 100%, minimum = 0% correct). Effect size calculations involved calculating the difference between post- and pre-treatment probe accuracy percentages with corrections made for variability (standard deviations in performance). The larger the effect size, the greater the change in performance from pre-treatment. Positive effect sizes = increases in accuracy & negative effect sizes = decreases in accuracy.

Change in accuracy of articulation of treated items as measured by percent increase in accuracy above the highest baseline measurement; production of words designated for treatment was measured repeatedly in non treatment probes prior to treatment, throughout all study phases, and at 10 weeks post treatment with percent accuracy calculated for each probe (0% to 100% correct). The highest percentage accuracy achieved in pre-treatment probes was subtracted from the percentage accuracy achieved at 10 weeks post-treatment to obtain change in accuracy value - this reflects change from maximum correct performance in baseline (pre-treatment). e.g., if in baseline probes, performance ranged from 10% to 30% accuracy and at post treatment performance was 90% accuracy, the change value would be 60% (90% minus 30%). A greater change value indicates greater change in articulation/production of words. Change could be positive (improved articulation) or negative (poorer articulation).

Percent change in articulatory accuracy of untrained items measured by change in percent accuracy over highest baseline value; production of words designated to NOT receive treatment (untrained items) was measured repeatedly in non treatment probes prior to treatment, throughout all study phases, and at 10 weeks post treatment with percent accuracy calculated for each probe (maximum = 100%, minimum = 0% correct). Effect size calculations involved calculating the difference between post- and pre-treatment probe accuracy percentages with corrections made for variability (standard deviations in performance). The larger the effect size, the greater the change in performance from pre-treatment. Positive effect sizes = increases in accuracy & negative effect sizes = decreases in accuracy.

All participants received Sound Production Treatment (SPT). Half the participants received SPT applied in a blocked fashion (SPT-B) first for 20 sessions. Following a 2 week washout period, those participants then received SPT applied in random fashion (SPT-R) for 20 sessions. The other half of the participants received the treatments in the opposite order.

Change in accuracy of articulation of trained items as measured from baseline to 10 weeks post treatment using effect size calculations as the indicator of magnitude of change; production of words designated for treatment was measured repeatedly in non treatment probes prior to treatment, throughout all study phases, and at 10 weeks post treatment with percent accuracy calculated for each probe (maximum = 100%, minimum = 0% correct). Effect size calculations involved calculating the difference between post- and pre-treatment probe accuracy percentages with corrections made for variability (standard deviations in performance). The larger the effect size, the greater the change in performance from pre-treatment. Positive effect sizes = increases in accuracy & negative effect sizes = decreases in accuracy.

20 speakers with chronic apraxia of speech and aphasia; effect sizes were calculated for each speaker for each treatment condition.

All participants received Sound Production Treatment (SPT). Half of the participants received SPT administered in a blocked fashion (SPT-B) first, followed by a 2 week washout period, and then SPT administered in a random fashion (SPT-R). The other half of the participants received both treatments administered in the reverse order. Participants were grouped together for analyses by treatment type; this was due to the fact that all participants received both treatments and were observed in the same way for both treatments regardless of which treatment was received first. There were not adverse events and consequently, no need to examine adverse events by arm.