UNASSIGNED: This study aimed to examine the internal structure and assess the psychometric properties of the Patient Health Questionnaire (PHQ-9) in a Puerto Rican sample of workers. This instrument is a nine-item questionnaire, which was conceptualized as a unidimensional structure; however, there are mixed results regarding this internal structure. This measure is used in the occupational health psychology context in organizations in Puerto Rico; nevertheless, there is little evidence of its psychometric properties with samples of workers.
UNASSIGNED: A total of 955 samples from two different study samples were used in this cross-sectional study design in which the PHQ-9 was used. We conducted confirmatory factor analysis, bifactor analysis, and random intercept item factor analysis to examine the internal structure of the PHQ-9. Moreover, a two-factor model was examined by randomly assigning items to the two factors. Measurement invariance across sex and the relationship with other constructs were examined.
UNASSIGNED: The best-fitted model was the bifactor model followed by the random intercept item factor. The five sets of two-factor models with items randomly assigned obtained acceptable and similar fit indices regardless of the items.
UNASSIGNED: The results suggest that the PHQ-9 appears to be a reliable and valid instrument to measure depression. The more parsimonious interpretation of its scores, for now, is a unidimensional structure. Comparison across sex appears to be useful in occupational health psychology research settings since the results suggest that the PHQ-9 is invariant regarding this variable.

UNASSIGNED: Depression is screened by many psychological tools, whereas the Patient Health Questionnaire-9 (PHQ-9) is one of the most commonly used self-administered tools. Uganda is a culturally diverse country with a wide variety of tribes, ethnic groups, languages, and disease conditions; it is urgent to know the psychometrics of the used PHQ-9 across different cohorts. However, there is no prior review to assess its reliability in this culturally diverse country, where this review fulfills the knowledge gap.
UNASSIGNED: Adhering to the PRISMA guideline, a systematic search was performed in several databases (i.e., PubMed, Africa-Wide Information, AJOL, and PsycINFO, among others), and a total of 51 articles were included in this review, confirming the study inclusion criteria (e.g., using the PHQ-9).
UNASSIGNED: The PHQ-9 has been used among individuals above 10 years and both genders, and the tool has been used most among the HIV patient group (n = 28). The tool is frequently administered by interviews and has been translated into several languages (mostly Luganda, n = 31). A cutoff of 10 was commonly used to identify clinical or major depression (n = 23), and its prevalence ranged from 8 to 67%. It has been validated for use in two populations, (i) HIV-positive participants and (ii) the general population attending a health facility. The sensitivity and specificity were 92 and 89%, respectively, at a cutoff score of 10, whereas 67 and 78%, respectively, at a cutoff score of 5. The Cronbach alpha ranged between 0.68 and 0.94.
UNASSIGNED: The PHQ-9 has been used in several studies in Uganda but validated in only two populations and is commonly used in one language. Thus, validation of the tool in various populations and languages is warranted to improve the tool\'s acceptance in Uganda.

Perinatal depression (PND) is a prevalent and disabling problem both during pregnancy and the postpartum period. The legacy screening measure has been the Edinburgh Postnatal Depression Scale (EPDS). This systematic review examines the validity of the PHQ-9 as a screener for PND.
The following databases were searched from January 2001 (when the PHQ-9 was first published) through June 2020: MEDLINE, Embase, and PsychInfo. Studies that compared the PHQ-9 to a criterion standard psychiatric interview were used to determine the operating characteristics of sensitivity, specificity and area under the curve (AUC). Studies comparing the PHQ-9 to the EPDS and other depression scales evaluated convergent validity.
A total of 35 articles were eligible for criterion (n = 10) or convergent (n = 25) validity. Meta-analysis of the 7 criterion validity studies using the standard PHQ-9 cut point ≥10 showed a pooled sensitivity, specificity and AUC of 0.84, 0.81 and 0.89, respectively. Operating characteristics of the PHQ-9 and EPDS were nearly identical in head-to-head comparison studies. The median correlation between the PHQ-9 and EPDS was 0.59, and categorical agreement was moderate.
The PHQ-9 appears to be a viable option for perinatal depression screening with operating characteristics similar to the legacy EPDS.

Depression is a leading cause of disability. International guidelines recommend screening for depression and the Patient Health Questionnaire 9 (PHQ-9) has been identified as the most reliable screening tool. We reviewed the evidence for using it within the primary care setting.
We retrieved studies from MEDLINE, Embase, PsycINFO, CINAHL and the Cochrane Library that carried out primary care-based depression screening using PHQ-9 in populations older than 12, from 1995 to 2018.
Forty-two studies were included in the systematic review. Most of the studies were cross-sectional (N=40, 95%), conducted in high-income countries (N=27, 71%) and recruited adult populations (N=38, 90%). The accuracy of the PHQ-9 was evaluated in 31 (74%) studies with a two-stage screening system, with structured interview most often carried out by primary care and mental health professionals. Most of the studies employed a cut-off score of 10 (N=24, 57%, total range 5 - 15). The overall sensitivity of PHQ-9 ranged from 0.37 to 0.98, specificity from 0.42 to 0.99, positive predictive value from 0.09 to 0.92, and negative predictive value from 0.8 to 1.
Lack of longitudinal studies, small sample size, and the heterogeneity of primary-care settings limited the generalizability of our results.
PHQ-9 has been widely validated and is recommended in a two-stage screening process. Longitudinal studies are necessary to provide evidence of long-term screening effectiveness.

This research sought to review studies that examined the factor structure of the PHQ-9 using a confirmatory factor analysis approach (Study 1); to review studies that tested the measurement invariance of the PHQ-9 (Study 2); to examine the psychometric properties of the European Portuguese version in the general population (Study 3).
Using PRISMA guidelines, a search was performed on Web of Science, PsycINFO, and Scopus from 2001 to August 2019. Assessment of eligibility criteria and data extraction were conducted by two independent researchers (Studies 1 and 2). In Study 3, data were collected from 1479 Portuguese adults, using a cross-sectional design. The BDI-II and the GDS-15 were administered to examine convergent validity.
The systematic review identified four-factor models of the PHQ-9 (Study 1). Nineteen studies supported a one-factor model, whereas 12 found evidence for a two-factor model. Both models were supported in general, clinical, psychiatric, and international samples. Study 2 identified ten studies that examined PHQ-9 measurement invariance across 18 groups. The PHQ-9 measurement invariance was fully supported across studies. Study 3 revealed that a two-factor model showed a close fit to data in the European Portuguese version of the PHQ-9. Measurement invariance, reliability, and convergent and divergent validity were also established.
Study 3 did not include a gold standard measure of depression to evaluate PHQ-9 diagnostic properties.
Conceptual implications of the findings are discussed, and recommendations for using the Portuguese version of the PHQ-9 as a screening measure in community settings are also highlighted.

UNASSIGNED: According to the World Health Organization, the alarming increase in rates of depression globally has become a serious concern. In 2010, the prevalence rate of depression in South Africa was 4.6%. Given the context of South Africa where the majority of the population have limited access to healthcare facilities and 59.3% of the population have access to the Internet, an online depression screening tool would have much to offer.
UNASSIGNED: To determine whether online depression screening tools would be suitable for use in South Africa.
UNASSIGNED: This study presents a systematic review of online depression screening tools to determine whether one would be suitable for use in South Africa. Articles were accessed from seven electronic databases from 1970 to 2018. All articles included in the review were critically appraised.
UNASSIGNED: A total of 17 articles met the inclusion criteria. From the results, there was only one screening tool available on an open access platform for use by the general population. The most common depression online screening tools were the Beck Depression Inventory-II (BDI-II), the Center for Epidemiology Studies Depression Scale (CES-D) and the Patient Health Questionnaire (PHQ-9). It was also evident that there were negligible differences in the psychometric properties of online versus paper versions of the online screening tools. Furthermore, there were very few studies that considered the African or South African population and no online screening tools for major depressive disorder (MDD) developed in these contexts.
UNASSIGNED: There appears to be a need for a depression screening tool to be adapted for online usage in South Africa. It is recommended that the online screening tool should be adapted from the three commonly used online depression screening tools: PHQ-9, CES-D and BDI-II.

Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (-0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.

OBJECTIVE: To investigate whether an authorship effect is found that leads to better performance in studies conducted by the original developers of the Patient Health Questionnaire (PHQ-9) (allegiant studies).
METHODS: Systematic review with random effects bivariate diagnostic meta-analysis. Search strategies included electronic databases, examination of reference lists and forward citation searches.
METHODS: Included studies provided sufficient data to calculate the diagnostic accuracy of the PHQ-9 against a gold standard diagnosis of major depression using the algorithm or the summed item scoring method at cut-off point 10.
METHODS: Descriptive information, methodological quality criteria and 2×2 contingency tables.
RESULTS: Seven allegiant and 20 independent studies reported the diagnostic performance of the PHQ-9 using the algorithm scoring method. Pooled diagnostic OR (DOR) for the allegiant group was 64.40, and 15.05 for non-allegiant studies group. The allegiance status was a significant predictor of DOR variation (p<0.0001).Five allegiant studies and 26 non-allegiant studies reported the performance of the PHQ-9 at recommended cut-off point of 10. Pooled DOR for the allegiant group was 49.31, and 24.96 for the non-allegiant studies. The allegiance status was a significant predictor of DOR variation (p=0.015).Some potential alternative explanations for the observed authorship effect including differences in study characteristics and quality were found, although it is not clear how some of them account for the observed differences.
CONCLUSIONS: Allegiant studies reported better performance of the PHQ-9. Allegiance status was predictive of variation in the DOR. Based on the observed differences between independent and non-independent studies, we were unable to conclude or exclude that allegiance effects are present in studies examining the diagnostic performance of the PHQ-9. This study highlights the need for future meta-analyses of diagnostic validation studies of psychological measures to evaluate the impact of researcher allegiance in the primary studies.