Table 1

Descriptive characteristics of algorithm studies13

StudySample characteristicsSample size and % depressedPHQ-9 characteristicsDiagnostic standarda) COI declaration
b) Funding
c) Relationship with original developers
(country, setting, age, sex)
Diez-Quevedo et al 22 Country: Spain
Setting: medical and surgical tertiary hospitals
Age (years): M=43 (SD=14.2)
Female: 45.6%
n=1003
Depressed: 8.2%
Administration: self-report
Language: Spanish
DSM-III-R
SCID
a) No COI declaration
b) Funding acknowledged (academic institutions)
c) Not acknowledged
Gräfe et al 23 Country: Germany
Setting: psychosomatic walk-in clinics and family practices
Age (years): male=41.9 (SD=13.8)
Female: 67.8%
n=528
Depressed: 29.2% psychosomatic patients; 6.16% medical patients
Language: German
Administration: self-report
DSM-IV
SCID
a) No COI declaration
b) Acknowledged funding from Pfizer
c) Not acknowledged
Lowe et al 24 Country: Germany
Setting: outpatient clinics and family practices
Age (years): male=41.7 (SD=13.8)
Female: 67.1%
n=501
Depressed: 13.2%
Administration: self-report
Language: German
DSM–IV
SCID
a) COI declaration ‘This study was supported by unrestricted restricted grants from Pfizer Germany and from the medical faculty of the University of Heidelberg Germany, and there are no COI’.
b) Acknowledged funding from Pfizer and academic institution
c) Not acknowledged
Muramatsu et al 27 Country: Japan
Setting: primary care and general hospital
Age (years): male=43.3 (SD=16.4)
Female: 59.5%
n=131
Depressed: 28.2%
Administration: self-report
Language: Japanese
DSM–IV
MINI
a) No COI declaration
b) Acknowledged funding from Pfizer
c) Acknowledged one of the developers of the PHQ-9: ‘The authors acknowledge Dr RL Spitzer’
Navinés et al 28 Country: Spain
Setting: general hospital (patients with chronic HCV)
Age (years): male=43.4 (SD=10.2)
Female: 28.6%
n=500
Depressed: 6.4%
Administration: self-report
Language: Spanish
DSM–IV
SCID
a) All authors declared that they had no COI.
b) Role of funding source declared
c) Not acknowledged
Spitzer et al 25 Country: USA
Setting: primary care
Age (years): male=46 (SD=17.2)
Female: 66%
n=3000 (585 received SCID)
Depressed: 10%
Administration: self-report
Language: English
DSM-III-R
SCID
a) No COI declaration
b) Acknowledged funding from Pfizer. ‘Drs Spitzer and Williams receive honoraria and consulting money from Pfizer, which has supported this work’.
c) N/A
Thekkumpurath et al 26 Country: UK
Setting: hospital (cancer patients)
Age (years): male=61
Female: 63%
n=782
Depressed: 6.3% (of the whole sample)
Administration: not stated
Language: English
DSM-IV
SCID
a) COI declaration: ‘Supported by Cancer Research UK’
b) As in a)
c) Not acknowledged
Ayalon et al 43 Country: Israel
Age (years): male=75 (SD=8.1)
Female: 40.5%
n=153
Depressed: 3.9%
Administration: researcher administered
Language: Hebrew
DSM-IV
SCID
a) COI declaration: ‘The project was funded by an Investigator’s Initiated Research Grant from Lundbeck International given to Dr Liat Ayalon. Lundbeck International had no other involvement in the project concept of design or in this paper. Per Bech has occasionally over the past 3 years until August 2008 received funding from and has been speaker or member of advisory boards for pharmaceutical companies with an interest in the drug treatment of affective disorders (AstraZeneca, Lilly, H Lundbeck A/S, Lundbeck Foundation and Organon)'.
b) Acknowledged funding from Lundbeck International
Eack et al 29 Country: USA
Setting: community mental health centres for children
Age (years): male=39.20 (SD 9.63)
Female: 100%
n=50
Depressed: 28%
Administration: self-report
Language: English
DSM-IV
SCID
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Fann et al 30 Country: USA
Setting: trauma hospital (inpatients with traumatic brain injury)
Age (years): male=42 (SD=17.9)
Female: 29.1%
n=135
Depressed: 16.3%
Administration: telephone-administered
Language: English
DSM-IV
SCID
a) No COI declaration
b) Funding acknowledged (academic institutions)
Gelaye et al 31 Country: Ethiopia
Setting: general hospital
Age (years): 34.9 (SD=11.6)
Female: 63.1%
n=363
Depressed: 12.6%
Administration: researcher-administered
Language: Amharic
DSM-IV
SCAN
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Gjerdingen et al 48 Country: USA
Setting: community
Age (years): male=29.3
Female: 100%
n=438
Depressed: 4.6%
Administration: telephone or self-report
Language: English
DSM-IV
SCID
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Henkel et al 44 Country: Germany
Setting: primary care
Age (years): not reported
Female: 74%
n=448
Depressed: 10%
Administration: self-report
Language: German
DSM-IV
CIDI
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Hyphantis et al 32 Country: Greece
Setting: hospital – rheumatology patients
Age (years): male=54.2 (SD=13.5)
Female: 74%
n=213
Depressed: 32.4%
Administration: researcher administered
Language: Greek
DSM-IV
MINI
a) No COI declaration
b) No funding acknowledgement
Inagaki et al 33 Country: Japan
Setting: general hospital
Age whole sample (years): male=73.5 (SD=12.3)
Female: 59.3%
n=104 out of 511 received MINI
Depressed: 7.4%
Administration: researcher administered
Language: Japanese
DSM-IV
MINI
a) COI declaration: ‘The authors declare that they have no competing interests’. b) Funding acknowledged (academic/health research institutions)
Khamseh et al 34 Country: Iran
Setting: diabetes clinic
Age (years): male=56.17 (SD=9.60)
Female: 51.9%
n=185
Depressed: 43.2%
Administration:self report
Language: Persian
DSM-IV
SCID
a) COI declaration: the authors declared no competing interests
b) Funding acknowledged (academic/health research institutions)
Lamers et al 45 Country: The Netherlands
Setting: primary care (elderly)
Age (years): male=71.4 (SD=6.90)
Female: 48.2%
n=713
Depressed: 10.7%
Administration:self report
Language: Dutch
DSM-IV
MINI
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Lotrakul et al 46 Country: Thailand
Setting: primary care
Age (years): male=45.0 (SD=14.30)
Female: 73.7%
n=279
Depressed: 6.8%
Administration:self report
Language: Thai
DSM-IV
MINI
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Persoons et al 35 Country: Belgium
Setting: hospital (otolaryngology patients)
Age (years): male=48.2 (SD=12.9)
Female: 65.6%
n=268 (97 received MINI)
Depressed: 16.5%
Administration: self-report
Language: Dutch
DSM-IV
MINI
a) No COI declaration
b) Funding acknowledged (academic/health research institutions) and Pfizer Belgium
Picardi et al 36 Country: Italy
Setting: hospital (dermatology inpatients)
Age (years): male=37.5
Female: 56%
n=141
Depressed: 8.5%
Administration: self-report
Language: Italian
DSM-IV
SCID
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Acknowledged Pfizer Italia SRL for providing the Italian version of the PHQ-9 and for permission to use it.
Stafford et al 37 Country: Australia
Setting: hospital (cardiology patients)
Age (years): male=64.1 (SD=10.3)
Female: 66%
n=193
Depressed: 18%
Administration: self-report
Language: English
DSM-IV
MINI
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Thombs et al 38 Country: USA
Setting: hospital (outpatients with coronary heart disease)
Age (years): male=67 (SD=11)
Female: 18%
n=1024
Depressed: 22%
Administration: not stated
Language: English
DSM
C-DIS
a) COI declaration ‘None disclosed’
b) Funding acknowledged (academic/health research institutions)
Thompson et al 39 Country: USA
Setting: patients with Parkinson’s disease
Age (years): 72.5 (SD=9.6)
Female: 42%
n=214
Depressed: 14%
Administration:self administered
Language: English
DSM-IV
SCID
a) No COI declaration
b) Funding acknowledged (academic/health research institutions)
Turner et al 40 Country: Australia
Setting: stroke patients
Age (years): 66.7 (SD=13.1)
Female: 47.2%
n=72
Depressed: 18%
Administration:self administered
Language: English
DSM-IV
SCID
a) COI declaration: disclosures ‘none’.
b) Funding acknowledged (academic/health research institutions)
van Steenbergen-Weijenburg et al 41 Country: The Netherlands
Setting: patients with diabetes
Age (years): male=61.8 (SD=13.6)
Female: 48.7%
n=197
Depressed: 18.8%
Administration: self administered
Language: Dutch
DSM-IV
SCID
a) COI declaration: ‘The authors declare that they have no competing interests’.
b) Funding acknowledged (academic/health research institutions)—‘this had no influence on the content of this article’.
Zuitthoff et al 47 Country: The Netherlands
Setting: primary care
Age (years): male=51 (SD=16.7)
Female: 63%
n=1338
Depressed: 13%
Administration: self-report
Language: Dutch
DSM-IV
CIDI
a) COI declaration ‘The authors declare that they have no competing interests’.
b) Funding acknowledged (academic/health research institutions)
  • CIDI, Composite International Diagnostic Interview,CIS-R, Clinical Interview Schedule;COI, conflict of interest; DSM, Diagnostic and Statistical Manual of Mental Disorders; MINI, Mini-International Neuropsychiatric Interview; N/A, not available; SCAN, Schedules for Clinical Assessments in Neuropsychiatry; SCID, Structured Clinical Interview for DSM Disorders.