Table 1

Review of Weiss Functional Impairment Rating Scale psychometric investigations

StudyWeiss et al 30Qian et al 24 Gajria et al 28Punyapas et al 22 Tarakçıoğlu et al 25 Dose et al 26 Canu et al 27 Takeda et al 21 Hadianfard et al 23
MeasureWFIRS-PWFIRS-PWFIRS-PWFIRS-P, WFIRS-SWFIRS-PWFIRS-P (excluded Risky Activities)WFIRS-SWFIRS-SWFIRS-S
LocationCanadaChinaNorth America, Australia, EuropeThailandTurkeyGermanyUSAJapanIran
Sample (n)Parents of youth with ADHD (209)Parents of youth with ADHD (123) and parents of normal youth (240)Parents of youth with ADHD from pharmacological clinical trials treating ADHD (2357)Parents (143) and their youth with ADHD (137)Parents of youth with ADHD (250) and healthy youth (250)Parents of youth with ADHD and/or ODD from randomised controlled trials examining a telephone-assisted self-help programme (264)Undergraduate adult college students (2098–16.5% met research cut-off for ADHD) and collateral reporters (CR) (262)Outpatient adults with ADHD (46), adult university students (889), adults without psychiatric disorders (104)Public secondary school students (386)
Age range (years) (% male)6–11ADHD 6–15 (84), non-ADHD group 6–16 (76)6–17 (75)4–18 (78)(M±SD) ADHD 9.61±2.18 (77), non-ADHD 9.85±2.12 (77)4–12 (80); parent’s M age 38.83 years (4)18–25 (33)ADHD 19–53 (52), students 18–45 (53), non-psychiatric 22–65 (38)12–18 (50)
Average total score (SD)1.1 (0.4)ADHD 0.77 (0.35), non-ADHD 0.29 (0.26)1.03 (0.47), 1.01 (0.45)1.00 (0.44)ADHD 0.88 (0.49), non-ADHD 0.35 (0.28)0.31 (0.29)
Internal consistency (α)Very strong:
Family, Total
Strong:
School, Life Skills, Self-Concept, Social Activities, Risky Activities
Strong:
Total and all domains
Very strong: Family, Total
Strong:
School, Self-Concept, Social, Life Skills, Risky Activities
Very strong:
WFIRS-P School, WFIRS-P Life Skills, WFIRS-P/S Self-Concept, WIFRS-S Social, WFIRS-P Risky Activities, WFIRS-P/S Total
Strong:
WFIRS-P/S Family, WFIRS-S Work, WFIRS-S School, WFIRS-S Life Skills, WFIRS-S Social, WFIRS-S Risky Activities
Very strong:
Total
Strong:
Family, School, Self-Concept, Social, Life Skills,
Moderate:
Risky Activities
Very strong: Total
Strong:
Family, School, Life Skills, Self-Concept, Social
Very strong:
Total, Work, School, Self-Concept, Social
Strong:
Family, Life Skills, Risky Activities
Very strong:
Self-Concept
Strong:
Family, Work, School, Life Skills, Social, Risky Activities
Very strong:
Self-Concept, Total
Strong:
Family, Work, School, Life Skills, Social, Risky Activities
Interdomain relationshipsAll domain-to-domain relationships were <r=0.67All domain-to-domain relationships were <r=0.66
Test–retest reliability
(1) Time between ratings
(2) Strength (r or ICC)
(1) 1–2 weeks
(2) Strong:
Family, School, Life Skills, Social Activities
Moderate:
Self-Concept, Risky Activities
(1) 2–3 weeks
(2) Strong:
Family, School, Life Skills, Self-Concept, Social Activities, Total
Moderate to strong:
Risky Activities
(1) 2–3 hours
(2) Strong:
WFIRS-P Total
Moderate:
WFIRS-S Total
(1) 4 weeks
(2) Very strong to strong: Total and all domains
(1) 2 weeks
(2) Strong:
Family, Work, School, Self-Concept
Moderate:
Life Skills, Social Activities, Risky Activities
(1) 2 weeks
(2) Strong:
School, Self-Concept, Social Activities, Risky Activities, Total
Moderate:
Family, Work, Life Skills
Concurrent/convergent validity (r)Moderate:
Total—CHIP:CE Risk Avoidance
Weak:
Total—ADHD-RS-IV Total, Total—CHIP:CE Satisfaction, Comfort, Resilience, Achievement
Very weak:
Total—GAF, Total—CGI-S
Weak:
Total—ADHD-RS-IV Total, all domains—ADHD-RS-IV Total
Moderate to weak:
Total—ADHD-RS-IV Total
Moderate to very weak:
Total—CGI-S
Strong:
Total—CGI-S
Moderate:
Total—PedsQL Total, Total—PedsQL Psychosocial Health, Total—CGAS, Total—T-DSM-IV-S ADHD Total
Weak:
Total—PedsQL Physical Health
Strong:
Total—CSS Impairment Total
Weak:
School—self-reported GPA
Strong:
Self-Concept—RSES-J, School—GAF, CAARS
Moderate:
Family, Work, Life Skills, Self-Concept Social—GAF, CAARS
Very weak:
Risky Activities—GAF, CAARS
Strong:
Total—PedsQL Total, Total—PedsQL Psychosocial Health
Weak:
Total—PedsQL Physical Health
Discriminant/divergent validity (r)Weak to very weak:
School, Life Skills—ADHD-RS-IV Hyperactivity impulsivity
ADHD group had higher scores in all domains and Total score compared with non-ADHD group***
Total and domain scores discriminated between groups categorised by overall ADHD severity: control group<mild<moderate<severe***Moderate:
Total—FBB-ADHS Total, FBB-SSV ODD
Only School and Work were more strongly associated with inattention when compared with relationships with depression, anxiety and stress, supporting the WFIRS as an ADHD-specific impairment measure.
ADHD group had higher impairment across more domains compared with non-ADHD group.
Moderate:
Self-Concept—BDI
Weak:
Family, Work, School, Life Skills, Social Activities, Risky Activities—BDI
Total and all domain scores were significantly higher in the ADHD group compared with the other groups***
Confirmatory factor analysis(school domain was excluded) Five factors; ADHD group CFI=0.89, RMSEA<0.08. Non-ADHD group CFI=0.97, RMSEA<0.08.Six factors; CFI=0.79–0.86, RMSEA=0.084–0.094Seven factors; CFI=0.95, RMSEA=0.061Five factors; CFI=0.93, RMSEA=0.05Seven factors; CFI=0.91, RMSEA=0.043Seven factors; CFI=0.60, RMSEA=0.08. When 12 items were removed, CFI=0.70, RMSEA=0.07
  • This does not represent a systematic review of all studies.

  • Magnitude definitions29: very strong= ≥±0.9, ±0.7 ≤ strong <±0.9, ±0.5 ≤ moderate <±0.7, ±0.3 ≤ weak <±0.5, very weak= ≤±0.3.

  • *P<0.05; **P<0.01; ***P<0.001.

  • †Only baseline data for Weiss et al [30] are reported.

  • ‡Gajria et al [28] sample was randomly split into two groups for replication and analysed at baseline and a follow-up visit.

  • ADHD, attention-deficit/hyperactivity disorder; ADHD-RS-IV, ADHD Rating Scale Version IV; BDI, Beck Depression Inventory; BRIEF, Behavior Rating Inventory of Executive Function; CAARS, Conners’ Adult ADHD Rating Scale; CFI, comparative fit index; CGAS, Children’s Global Assessment Scale; CGI-S, Clinical Global Impressions-Severity; CHIP-CE, Child Health Illness Profile: Child Edition; CSS, Current Symptom Scale; DASS, Depression Anxiety Stress Scale 21; FBB-ADHS, Symptom Checklist for Attention-Deficit/Hyperactivity Disorder; FBB-SSV, Symptom Checklist for Oppositional Defiant and Conduct Disorder; GAF, Global Assessment Functioning; ICC, intraclass correlation coefficient; M, mean; ODD, oppositional defiant disorder; PedsQL, Pediatric Quality of Life Inventory; RMSEA, root mean square error of approximation; RSES-J, Rosenberg Self-Esteem Scale Japanese Version; SDS, Sheehan Disability Scale; T-DSM-IV-S, Turgay’s DSM-IV-based ADHD and Disruptive Behavior Disorders Screening Scale-Parent; WFIRS-P, Weiss Functional Impairment Rating Scale-Parent; WFIRS-S, Weiss Functional Impairment Rating Scale-Self.