1. Case-finding of lifestyle and mental health problems in primary care: validation of the 'CHAT' tool
NAPCRG Vancouver 2007
Felicity Goodyear-Smith, Bruce Arroll, Nicole Coupe, C Raina Elley, Sean Sullivan
Department of General Practice
& Primary Health Care
University of Auckland

2. Background
In order to prevent disease, first you have to detect risk factors
Few validated tools for lifestyle & mental health risk factors in primary care
Need for brief case-finding tools

3. CHAT: Case-finding & ‘Help’ Assessment Tool
Lifestyle & mental health screening assessment tool for use in primary care
Smoking
Alcohol misuse
Other drug misuse
Problem gambling
Depression
Anxiety
Abuse
Anger
Physical inactivity
Issues around eating

4.  No  Yes but not today  Yes
The ‘HELP’ question
For each question or pair of questions:
If yes to either or both of these 2 questions, do you want help with this?
 No  Yes but not today  Yes

5. Evaluation of CHAT tool
Initial study assessed acceptability of tool
Participants: >2,500 consecutive patients from 20 randomly selected urban & 11 rural family physicians & 20 urban & rural practice nurses (50/practitioner)

6. Evaluation of CHAT Results:
Patients wanting help today (0.5 to 13.5%) not overwhelming
Well accepted by patients, objections to specific questions <1%
Drs & nurses would use tool once available
Goodyear-Smith et al (2004) New Zealand Medical Journal 117 (1205)

7. Value of ‘HELP’ Question
Depression study: Adding question inquiring if help is needed to 2 questions on depression increases specificity (reduces false positives)
Arroll, Goodyear-Smith et al (2005). BMJ, 25 Sep doi:1136/bmj C

8. To assess validity of CHAT against composite gold standard
Aim of current study
To assess validity of CHAT against composite gold standard

9. Method Conducted according to STARD statement for diagnostic tests
Setting: Primary care practices in Auckland
Participants: 1000 consecutive adult patients completed CHAT & composite gold standard
Analysis: Sensitivities, specificities & likelihood ratios

10. Case prevalence
Sensitivity %
Specificity LR
+ test
Nicotine dependency
9.8% 89 97
10.6
Problem drinking
14.5% 79 99 12
Drug misuse
2.0% 58 16
Problem gambling
1.8% 78 30
Major depression
5.3% 96 95 10
Anxiety
10.9% 88 9

11. Case prevalence
Sensitivity
Specificity
LR+
Verbal abuse
2.6% 62 99 12
Physical abuse
0.6% 80 94 13
Anger 2% 77 98 16
Inactivity
55% 31 18
Eating disorder
25% 73 89 3

12. Inactivity
Reason for low sensitivity: Format of question was reversed: confusing & led to inverted response
Eating disorder
Reason for high prevalence: Gold standard was not precise enough - probably identifying concerns about being overweight & eating patterns rather than formal eating disorder

13. Addition of ‘HELP’ question
Specificity
Nicotine dependency: 89%  97%
Problem drinking: 88%  99%
Other drug use: 97%  99%
Gambling: 97%  99%
Depression: 69%  95%
Anxiety: 74%  99%
Verbal abuse: 98%  99%
Verbal aggression: 92%  99%

14. LR of ‘Help’ question: example
Nicotine dependency
LR +ve
Help today
11.5
Help either today or later
10.6
Help but not today
10.4
No help
0.57

15. Discussion Limitations: Inactivity question inverted – confusion
Eating gold standard imprecise
Small numbers for some conditions (wide CI)
Pragmatic gold standard instruments

16. Discussion Strengths: Good generalisability:
Very low decline rate
Consecutive patients
Most conditions had tight confidence intervals
Patients completed gold std for all conditions

17. CHAT Quick to use Acceptable Valid
Summary
CHAT
Quick to use
Acceptable
Valid

18. Further developments…
Integrate CHAT into electronic medical record
Self-administration by handheld or touch screen in waiting room
Add automatic diagnostic tool if CHAT item +ve
Conduct RCT to assess effect of CHAT on clinical outcomes

19. Thank you
Any questions?