BOX 1–1 Guidelines Used to Evaluate Studies

Every research report considered by the committee was assigned to one category (I–IV) for each area (A, B, and C).

  1. Internal Validity: Control for nonspecific factors, such as maturation, expectancy, experimenter artifacts

    1. Prospective study comparing the intervention to an alternative intervention or placebo in which evaluators of outcome are blind to treatment status

    2. Multiple baseline, ABAB design, or reversal/withdrawal with measurement of outcome blind to treatment conditions or pre-post design with independent evaluation

    3. Pre-post or historical designs or multiple baseline, ABAB, reversal/ withdrawal not blind to treatment conditions

    4. Other

  1. External Validity/Selection Biases

    1. Random assignment of well-defined cohorts and adequate sample size for comparisons

    2. Nonrandom assignment, but well-defined cohorts with inclusion/ exclusion criteria and documentation of attrition/failures; additionally, adequate sample size for group designs or replication across three or more subjects in a single-subject design

    3. Well-defined population of three or more subjects in single-subject designs or sample of adequate size in group designs

    4. Other

  1. Generalization

    1. Documented changes in at least one natural setting outside of treatment setting (includes social validity measures)

    2. Generalization to one other setting or maintenance beyond experimental intervention in natural setting in which intervention took place

    3. Intervention occurred in natural setting or use of outcome measures with documented relationship to functional outcome

    4. Not addressed or other

guidelines were used by both committee members and commissioned paper authors in their reviews of the literature. Figures 1–1, 1–2, and 1–3 present summarized data from journal articles cited within the areas addressed during the workshops (communication, social development, problem behaviors, intervention methods, and sensorimotor develop-



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