Box 8-3

Percentage of 19 Studies Reporting External Validitya Dimensions, 1980-2004

External Validity Dimensionb

Percent Reporting

Reach and Representativeness

 

Individual Participants

 

Description of targets

100

Individual inclusion/exclusion criteria

90

Participation rate

63

Representativeness

10

Setting

 

Description of targets

95

Setting inclusion/exclusion criteria

11

Participation rate

22

Representativeness

0

Delivery Staff

 

Participation rate

5

Implementation and Adaptation

 

Consistency of implementation

26

Staff expertise or training

89

Variations in implementation by staff

5

Program adaptation

42

Outcomes of Decision Making

 

Outcomes compared with goal

37

Adverse consequences

32

Moderation of effect by participant characteristic(s)

53

Moderation of effect by staff/setting

10

Number of sessions or time needed to deliver intervention

68

Costs

0

Maintenance and Institutionalization

 

Long-term effects (at least 12 months)

74

Program sustainability

0

Attrition rate

100

Differential attrition by condition tested

21

Drop-out representativeness

42

a External validity is defined according to Leviton (2001).

b See Green and Glasgow (2006) for a detailed description of coding dimensions.

SOURCE: Reprinted from Klesges et al., Copyright © 2008, with permission from Elsevier.



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