Incontinence Quality of Life Questionnaire (I-QOL)

Clinical Summary

Jump to: Tool Description | Interpretability | Measurement Property Summary

Tool Description

  • measures the effect of urinary incontinence on quality of life.
  • The I-QOL is divided into 3 subscales:

1) avoidance and limiting behavior (ALB)
2) psychosocial impact (PSI)
3) social embarrassment (SE). 

ICF Domain:

Quality of Life.

Number of Items:

22

Brief Instructions for Administration & Scoring

Administration:

  • self-report questionnaire.
  • Subjects use a 5-point response scale with values ranging from 1 (extremely) to 5 (not at all).

Equipment:None.

Scoring:

  • A mean score for each subscale is calculated (averaging the scores for the items in each subscale) as well as a total score for all 22 items (sum of all subscale scores).
  • The scores are then transformed to a ‘Scale score’ ranging from 0-100 points for ease of interpretation: Scale score = (sum of the items – lowest possible score)/possible raw score range X 100

Interpretability

MCID: MID (Minimally Important Difference) is approximately 4 points when defined as that corresponding to a small effect size (0.2 SD at baseline) and approximately 11 points when defined as corresponding to a medium effect size (0.5 SD at baseline).
SEM: ranged from 8-11 points.
MDC: not established

  • For all items, higher scores indicate less impact of urinary tract infections on quality of life.
  • No normative data has been established for the SCI population.

Languages:

The instrument has been translated into more than 20 European, Asian, North and South American, and African languages.

Training Required:

None, but reading the user manual is recommended.

Availability:

The I-QoL can be found in the original article (Schurch et al; 2007); however no information was found on how to access the user manual.  The IQOL is copyrighted and can be purchased at http://depts.washington.edu/seaqol/IQOL.

Clinical Considerations

  • The I-QOL is a highly used and widely recommended scale. Among other populations, the scale has been shown to be reliable, valid, and responsive to change. No ceiling effects have been reported and it is suitable for both men and women.
  • The scale was originally developed for the general population; subsequently, some items are not applicable for individuals with SCI.
  • The questionnaire is easy to understand and poses little respondent burden. However, the assessment cannot be completed by proxy.

Measurement Property Summary

# of studies reporting psychometric properties: 1

Reliability:

  • Internal consistency is excellent for the I-QOL total score (Cronbach’s a=0.93) as well as the 3 subscales (Cronbach’s a=0.79-0.89).

[Schurch et al. 2007]

Validity:

  • Correlations between SF-36 and I-QOL scores at the end of the study (week 24) were substantial for most SF-36 domains and tended to be stronger and more likely to be significant than those at screening.
  • Correlations between SF-36 and I-QOL scores at week 24 were adequate and strongest for mental health (Pearson’s r =.45-.59), social functioning (Pearson’s r= .43-.54), and vitality (Pearson’s r =.36-.54)

[Schurch et al. 2007]

Responsiveness:

  • No values were reported for the responsiveness of the I-QOL for the SCI population.

Floor/ceiling effect:

  • There were no ceiling effects for I-QOL total and subscales, and a small floor effect for the Social Embarrassment domain (8.9% subjects had lowest score).

[Schurch et al. 2007]

Reviewer

Dr. Vanessa Noonan, Christie Chan

Date Last Updated:

Feb 1, 2013