Contemporary UD Study Kroenke et al

Question 1

Contemporary Study: Kroenke et al. 2008 UD Procedure

Answer 1

Used the Behavioural Risk Factor Surveillance Survey. This is a monthly telephone survey conducted in all USA states.

BRFSS involves trained interviewers who collected data on health and risk related behaviours linked to diseases and injuries.

Question 2

Contemporary Study: Kroenke et al. 2008 UD Sample

Answer 2

Sample: 198,678 randomly selected adults.

Questions were related to diagnosis and severity of anxiety and depression and were asked in 38 states as well as the District of Columbia, Puerto Rico and US Virgin Islands.

Question 3

Contemporary Study: Kroenke et al. 2008 UD Procedure PHQ-8

Answer 3

This is the Patient Health Questionnaire.
Interviewers used an eight-item version of this that covered eight of the DSM-IV symptoms of Unipolar Depression.

Interviewees gave the number of days in the past two weeks’ that they experienced each of the 8 symptoms.
Researchers assigned zero points for items experienced on days 0-1, one for 2-6 days, two for 7-11 days, and three for 12-14 days. A total score was given /24.

Question 4

Contemporary Study: Kroenke et al. 2008 UD Procedure HRQoL

Answer 4

Researchers analysed three questions from BRFSS.
A self-assessment measure of each respondent’s health over the previous 30 days.

Respondents gave no. of days when physical and mental health were not good and when it stopped them from doing normal activities.

5 additional questions asked in three US states only.

Question 5

Contemporary Study: Kroenke et al. 2008 UD Findings PHQ-8

Answer 5

PHQ-8:
8,476 had MDD (4.3%).
Any depression is 18,053 (9.1%).
Cutpoint method is 17,040 (8.6%).

Question 6

Contemporary Study: Kroenke et al. 2008 UD Findings HRQoL and Depression:

Answer 6

Depressed reported more days of impaired HRQoL than nondepressed, across all types of HRQoL.

No difference between the two definitions of depression (algorithm and cutpoint) in the number of impaired HRQoL days from both respondents.

Question 7

Contemporary Study: Kroenke et al. 2008 UD Conclusion

Answer 7

Prevalence rates of depression using PHQ-8 are accurate or slightly conservative estimates of depression in the US. PHQ-8 is useful in research contexts.

PHQ-8 conceives the disorder as a dimension along which people vary in terms of severity.

Gives PHQ-8 an advantage because they anticipated that the forthcoming DSM-V would introduce a dimensional element to diagnosis.

Question 8

What did Kroenke suggest about the PHQ-8 in regards to measuring severity?

Answer 8

the PHQ-8 is just as good at measuring severity and a better instrument for diagnosing depressive disorders under DSM-IV criteria.

Question 9

Contemporary Study: Kroenke et al. 2008 UD Strength

Answer 9

Reliable as it used standardised procedures like a standardised questionnaire, trained interviews, following a detailed protocol.

Respondents completed a consent form and data kept confidential.

Question 10

Contemporary Study: Kroenke et al. 2008 UD Weakness

Answer 10

Ethical issues as questions are very personal and likely to cause stress.

Unrepresentative as excludes anyone in institutions or without a phone.

Question 11

Contemporary Study: Kroenke et al. 2008 UD Application

Answer 11

Prevent depression. Use to screen large numbers of people and help identify early signs and symptoms of depressive disorders.