|Year : 2018 | Volume
| Issue : 3 | Page : 219-224
Adaptation of the patient health questionnaire-8 as a self-rated suicide risk screening instrument among the family caregivers of Nigerian patients with depressive disorders
Olutayo Aloba1, Olayinka Ajao2, Tolulope Aloba3
1 Department of Mental Health, Obafemi Awolowo University Teaching Hospital Complexes, Ile-Ife, Osun State, Nigeria
2 Department of Nursing Sciences, Ekiti State University Teaching Hospital, Ado-Ekiti, Nigeria
3 Department of Nursing Sciences, Obafemi Awolowo University, Ile-Ife, Osun State, Nigeria
|Date of Web Publication||27-Sep-2018|
Dr. Olutayo Aloba
Department of Mental Health, Obafemi Awolowo University Teaching Hospital Complexes, Ile-Ife, Osun State
Source of Support: None, Conflict of Interest: None
Background: The assessment of suicide risk has been neglected among the family caregivers (FCs) of patients with depressive disorders. Objectives: The objective was to examine the validity, reliability, and suicide risk screening characteristics of the PHQ-8 in a sample of Nigerian FCs of patients with psychiatric disorders specifically depressive disorders. Methods: A total of 262 FC-patient dyads were consecutively recruited adopting a convenience sampling technique from two tertiary healthcare facilities in Southwestern Nigeria. Their FCs completed the PHQ-8, the General Health Questionnaire-12 (GHQ-12), and the Zarit Burden Interview (ZBI). Suicide risk level was assessed by interviewing them with the Mini International Neuropsychiatric Interview (MINI) suicidality module. The patients completed the Hamilton Depression Rating Scale (HDRS), and their functioning was evaluated with the Global Assessment of Functioning (GAF) Scale. Results: The Cronbach's alpha for the PHQ-8 items was 0.80. It demonstrated satisfactory construct validity with the FC score on the ZBI (P < 0.001), GHQ-12 (P < 0.001), and patients' HDRS (P < 0.001), and GAF (P < 0.001) scores. Logistic regression revealed that only the FCs' PHQ-8 score was positively associated with their suicide risk status. Applying the receiver operating characteristics curve, the best cutoff score for those with high-suicide risk was 8 (sensitivity 0.889, specificity 0.850). Conclusions: The PHQ-8 has satisfactory screening properties as a suicide risk assessment tool among the FCs of Nigerian patients with depressive disorders.
Keywords: Nigerian family caregivers, Patient Health Questionaire-8, sensitivity, specificity, suicide risk
|How to cite this article:|
Aloba O, Ajao O, Aloba T. Adaptation of the patient health questionnaire-8 as a self-rated suicide risk screening instrument among the family caregivers of Nigerian patients with depressive disorders. Indian J Soc Psychiatry 2018;34:219-24
|How to cite this URL:|
Aloba O, Ajao O, Aloba T. Adaptation of the patient health questionnaire-8 as a self-rated suicide risk screening instrument among the family caregivers of Nigerian patients with depressive disorders. Indian J Soc Psychiatry [serial online] 2018 [cited 2022 Aug 16];34:219-24. Available from: https://www.indjsp.org/text.asp?2018/34/3/219/242361
| Introduction|| |
It has been estimated that suicide will account for 2.4% of the global burden of disease by the year 2020. The assessment of suicide risk among the family caregivers (FCs) of patients with psychiatric disorders has been neglected. This is despite the fact that previous studies have established strong associations between poor psychological and physical well-being and the provision of informal care for patients with long-term medical problems., The majority of studies evaluating suicidality among FCs had focused mainly on those providing care for patients with Alzheimer's dementia.,,, Recently, the FCs providing care and support for patients with long-term medical problems such as organic mental disorders and oncological disorders have been described as “forgotten.”
The eight-item Patient Health Questionnaire (PHQ-8) is a very brief self-rated assessment of the severity of depressive symptoms. The PHQ-8 is comprised of eight out of the nine items that made up the criteria for the diagnosis of major depressive episode according to the fourth version of the Diagnostic and Statistical Manual of Mental Disorders. An extensive electronic literature search revealed that the validity and reliability of the PHQ-8 in addition to its usefulness as a suicide risk screening measurement have not been examined among any population in Nigeria. The aim of this study was to examine the reliability and validity of the PHQ-8 and in addition to obtain the preliminary evidence that will support its suitability as a suicide risk assessment tool among the FCs of Nigerian patients with psychiatric disorders specifically depressive disorders.
| Methods|| |
A total of 262 FC-patient dyads were recruited over a period of 6 months from the mental health outpatient clinics of two university teaching hospitals in Southwestern Nigeria between November 2016 and April 2017. We adopted a convenience sampling technique in which the FCs who accompanied their patient relatives were consecutively recruited if they fulfill the study inclusion criteria. For the FCs to be eligible, first, he or she must be aged 18 years and above and without any financial gain and has being providing care for the patient for the past 6 months. Second, he or she must not have a current or previous history of a chronic medical or psychiatric disorder. Third, they must give consent to participate in the study. Inclusion criteria for the patients include aged 18 years and above, must have been an outpatient in these centers for at least 6 months and the severity of the affective and psychopathological symptoms presented by the patients during the outpatient clinics is not to the level where it will affect their ability to give consent.
The research protocol was granted ethical approval by the Ethics and Research Committees of the two healthcare institutions.
The FCs completed the following measures.
Patient Health Questionnaire-8
The PHQ-8 is a commonly utilized tool for the assessment of the severity of depressive symptoms in developed countries. It consists of eight items. Each of the items is scored according to a 4-point Likert scale (not at all – 0 to nearly every day – 3). The total score ranges from 0 to 24. The greater the severity of the depressive symptoms, the higher the score on the questionnaire. The PHQ-8 was extracted from the PHQ-9 after the ninth item that enquired about suicide-related behavior was eliminated due to its sensitive nature.
Zarit burden interview
The FCs' subjective level of burden was measured with the Zarit burden interview (ZBI). The scale consists of 22 items, each measured on a 5-point Likert scale, ranging from 0 (never) to 4 (almost always). The higher the score, the more severe the level of subjective burden being experienced by the FCs. Satisfactory validity and reliability have been demonstrated among the Nigerian FCs of patients with chronic mental disorders.,,,,
Mini International Neuropsychiatric Interview suicidality module
The Mini International Neuropsychiatric Interview (MINI) suicidality module consists of six items designed to evaluate the risk of suicide via a number of questions divided into two aspects (in the past 1 month and lifetime). The five items designated to the evaluation of suicide risk in the preceding 1 month include C1: Think that you would be better off dead or wish you were dead? C2: Want to harm yourself? C3: Think about suicide? C4: Have a suicide plan? and C5: Attempt suicide? Only one item evaluates the lifetime suicide risk; C6: Did you ever make a suicide attempt? The response to each of the six items is either “yes” or “no.” An indication of “yes” to either C4 or C5 or both items C3 and C6 indicates high-suicide risk. A positive response to C1 or C2 or C6 indicates low-suicide risk while a positive response to C3 or both C2 and C6 reflects moderate-suicide risk. The items of the MINI suicidality module were employed as the “gold standard” against which the sensitivity and specificity of the PHQ-8 will be examined for the detection of the FCs with high-suicide risk. The suicidality module of the MINI has been utilized previously in the assessment of suicide risk among the clinical and nonclinical populations in Nigeria.
General Health Questionnaire-12
The FCs also completed the General Health Questionnaire-12 (GHQ-12), a brief scale for the assessment of psychological distress that has been demonstrated to possess satisfactory psychometric characteristics among the Nigerian general population. The binary scoring method of 0-0-1-1 was adopted in this study. The study that examined the validity of the GHQ-12 in the Nigerian population reported a total cutoff score of 3 and above as indicative of psychological distress. This total cutoff score has also been utilized in the previous studies that involved the general, and clinical populations in Nigeria.
The study instruments completed by the patients include as follows:
Global Assessment of Functioning Scale
The clinician-administered Global Assessment of Functioning (GAF) scale was used to measure the level of patients' functioning. Scores on the scale range from 0 to 100, with higher functioning indicated by higher scores.
Hamilton Depression Rating Scale
This 17-item scale was objectively applied to measure the severity of depressive symptoms over the preceding week among the patients. Higher scores reflect greater depressive symptoms severity.
Descriptive statistics such as frequencies (percentages) and means (standard deviations) were used to depict the FCs' and patients' sociodemographic data and performance on the study measures. First, to examine the reliability of the PHQ-8 among the FCs, we examined the correlation coefficients of the scale's items by calculating the Cronbach's alpha. Second, we examined the best cutoff total score on the PHQ-8 that will optimally classify the high-suicide risk FCs. We achieved this by calculating the area under the curve (AUC) that will be associated with the best sensitivity and specificity values in relation to Youden's index. The MINI suicidality module was adopted as the “gold standard,” against which we examined the discriminatory ability of the PHQ-8 among the FCs. A more satisfactory discriminatory ability of the PHQ-8 in identifying the high-suicide risk FCs will be reflected by an AUC closer to one. The other parameters that we calculated in addition to the sensitivity and specificity values include the positive and negative predictive values (PPV and NPV), and the positive and negative likelihood ratios (LR + ve and LR − ve). Third, we explored the construct validity of the PHQ-8 through correlational analyses with the FCs' scores on the ZBI and GHQ-12 and patients' performance on the Hamilton Depression Rating Scale (HDRS) and GAF. Finally, we demonstrated the discriminative validity of the PHQ-8 in relation to the suicide risk categories among the FCs applying logistic regression analysis. Statistical analyses were conducted with the 21st version of the Statistical Package for the Social Scientists (SPSS, IBM Corp, Armonk, New York, USA). All tests were two-tailed and P < 0.05 was considered statistically significant.
| Results|| |
As seen in [Table 1], the mean age of the FCs in this study was 52.10 (standard deviation [SD] 14.12) years. Majority (71.4%) of them were females. Among the FCs, the mean PHQ-8 score was 4.39 (SD 4.13). The internal consistency of the PHQ-8 items evaluated with Cronbach's alpha was 0.80. When we examined the psychometric characteristics of the PHQ-8 against the MINI suicidality module categorization with receiver operating characteristics (ROC) analysis, we noted that the questionnaire demonstrated satisfactory discriminatory ability in the identification of the FCs who belonged to the high-suicide risk category. The best total cutoff score on the PHQ-8 to identify those in the high-suicide risk group was 8. At this cutoff score, the sensitivity and specificity were 0.889 and 0.850, respectively. Youden's index (0.739) and accuracy (0.870) were highest at this cutoff score. The AUC was 0.940 (95% confidence interval = 0.892–0.988). The performance of the PHQ-8 against the MINI suicidality module categorization is depicted in [Table 2] and the ROC curve is shown in [Figure 1]. As shown in [Table 3], the construct validity of the PHQ-8 was supported among the FCs through its statistically significant correlations with the FCs' scores on the ZBI (r = 0.504, P < 0.001) and GHQ-12 (r = 0.675, P < 0.001) and the patients' scores on the HDRS (r = 0.675, P < 0.001) and the GAF (r = −0.328, P < 0.001). [Table 4] depicts a positive relationship between the PHQ-8 and the probability of belonging to the high-suicide risk group among the FCs. A one-point increase on the PHQ-8 multiplies the odds of belonging to the high-suicide risk group among the FCs by a factor of 1.408. No statistically significant associations were observed between the FCs' suicide risk groups and the ZBI, GHQ-12, and patients scores on the HDRS and GAF.
|Table 1: Sociodemographic data of the family caregivers and patients (n=262)|
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|Table 2: Psychometric characteristics of the Patient Health Questionnaire-8 at different cutoff scores against the mini international neuropsychiatric interview suicidality module categorization|
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|Figure 1: Receiver operating characteristics curve of the Patient Health Questionnaire-8 (at a cutoff score of 8) against the family caregivers' Mini International Neuropsychiatric Interview suicidality module risk categorization (area under the curve = 0.940; standard error = 0.024; 95% confidence interval = 0.892–0.988)|
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|Table 3: Construct validity (correlational analyses) of the Patient Health Questionnaire-8 among the family caregivers|
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| Discussion|| |
The aim of this study was to examine the validity and reliability of the PHQ-8 as well as its usefulness as a self-rated suicide risk screening tool in a cross-sectional sample of FCs of Nigerian patients with psychiatric disorders specifically those receiving treatment for depressive disorders. We explored the ability of the questionnaire to correctly categorize those Nigerian FCs positive for high-suicide risk from those identified as negative for high-suicide risk according to the MINI suicidality module. We examined the ROC curve to determine the optimal cutoff score on the PHQ-8 that would correctly identify in terms of sensitivity and specificity the FCs with high-suicide risk. Altogether, the findings in our study revealed that the PHQ-8 may be applicable as a self-rated suicide risk screening tool among the Nigerian FCs of patients with depressive disorders.
In terms of reliability, the items of the PHQ-8 among the Nigerian FCs demonstrated satisfactory internal consistency with a Cronbach's alpha of 0.80. A Cronbach's alpha of 0.70 and greater is indicative of satisfactory reliability and value exceeding 0.90 reflects the possibility of redundant items within the scale. The reliability of the PHQ-8 among the Nigerian FCs is further supported by the modestly high-corrected item total correlations (0.414–0.628).
As indicated by the highest Youden's index value, an aggregative total cutoff score of 8 on the PHQ-8 was associated with the best sensitivity and specificity balance for the correct identification of the FCs categorized as belonging to the high-suicide risk group. At a cut-off score of 8, the PHQ-8 had a sensitivity (positive for high suicide risk) and specificity (negative for high suicide risk) of 0.889 and 0.850 respectively in relation to the FCs MINI suicide risk status. It has been suggested that the minimum requirement for the acceptability of the sensitivity of a screening instrument should be >70%., Likewise, to reduce over referrals, the specificity of a screening tool should be at a minimum of 80%. Therefore, applying the PHQ-8 as a self-rated suicide risk screening instrument among the Nigerian FCs will be associated with the lowest rate of false positives at a cutoff score of 8. In addition, this cutoff score has the highest PPV and NPV. A PPV of 0.856 indicates the percentage (85.6%) of the Nigerian FCs identified as having high-suicide risk who truly have a high risk of suicide. Likewise, the NPV of 0.884 refers to the percentage (88.4%) of the respondents identified as not in the category of those with high-suicide risk who truly are not highly suicidal. Thus, the PPV and the NPV at the cutoff score of 8 reflects a small percentage of false positives and false negatives among the respondents in relation to their suicide risk assessment.
This cutoff score was associated with a modest likelihood ratio for a positive test (LR +ve) and smallest likelihood ratio for a negative test (LR −ve). The LR +ve value indicates a moderate probability that those who are truly positive for high-suicide risk will be correctly classified at a cutoff score of 8. In addition, the smallest LR −ve at a cutoff score of 8 on the PHQ-8 reflects the strong probability that the Nigerian FCs of patients with depressive disorders who do not have a high risk for suicide (true negatives) will be correctly classified. The value of the AUC of the ROC curve we obtained is another evidence that supports the discriminatory ability of the questionnaire at a total cutoff score of 8 in differentiating between the FCs positive for high-suicide risk and those negative for high-suicide risk. The AUC of 0.94 indicates that 94.0% of the time, an FC randomly selected from those categorized as positive for high-suicide risk will have a total score on the PHQ-8 that exceeds 8 compared to those categorized as negative for high-suicide risk. An AUC >0.80 supports the usefulness of a measurement as a screener.
The PHQ-8 among the FCs demonstrated modestly satisfactory construct validity. The direction and strength of the relationships between the PHQ-8 and the other study measures completed by the FCs (ZBI and GHQ-12) and the patients (HDRS and GAF) were all as statistically expected. Higher PHQ-8 scores were associated with higher burden (ZBI) and psychological distress (GHQ-12) among the FCs. The highest positive correlation we observed between PHQ-8 and GHQ-12 among the FCs appears important, since high scores on the GHQ-12 reflect the likelihood of the presence of a psychiatric morbidity. Likewise, higher PHQ-8 scores among the FCs correlated positively with higher depressive symptomatology (HDRS) and negatively with functioning (GAF) among the patients. These findings supporting the construct validity of the PHQ-8 among the Nigerian FCs also appear to point to some clinically relevant issues. From the correlations depicted in [Table 3], it thus appears that the clinical stability and functioning of the patients have an important relationship with the psychological well-being of the FCs. We are of the opinion that additional studies are still needed in our environment to further explore the psychological variables that influence the well-being of FCs of patients with other types of psychiatric and medical disorders. We also examined the discriminative validity of the PHQ-8 in relation to the suicide risk status of the FCs. Logistic regression reflects a positive relationship between PHQ-8 and the probability of belonging to the high-suicide risk category among the FCs. None of the other study measures in this study had statistically significant relationship with the FCs' suicide risk status.
We want to state that the utilization of the PHQ-8 as a self-rated suicide risk assessment tool among the FCs in this study is the first step in a more thorough process geared toward the reduction of suicide risk among the respondents, in that those with high cumulative scores on the questionnaire will need to be subjected to further evaluations. We want to point out a number of short-comings regarding our study. First, our sample size of FCs was rather modest; thus, there is need for caution in generalizing our findings to other FCs of patients with depressive disorders within the Nigerian community in general. Second, we focus only on the FCs of patients who were on the treatment for depressive disorders. The strength of our study is that it is the first in Nigeria and Sub-Sahara Africa to explore the reliability and validity of the PHQ-8 among the FCs of patients receiving treatment for depressive disorders. Another strength is that this is the first study to examine the suicide risk screening characteristics of the PHQ-8 among this group of Nigerian FCs. In addition, we adopted a structured interview method as the “gold standard” against which we investigated the screening characteristics of the PHQ-8. In a developing country such as Nigeria where only a few individuals are trained in the use of structured interview techniques such as the MINI, the availability of a subjectively completed suicide risk assessment tool will be of tremendous benefits toward the identification of the high-suicide risk Nigerian FCs. Furthermore, a brief, quick to complete, and publicly available scale such as the PHQ-8 will be quite useful among FCs in the context of a busy psychiatric clinic. A comparison of our study findings was rather difficult since this is the only study to have explored the suicide risk screening properties of the PHQ-8 among the Nigerian FCs of patients with depressive disorders. Additional studies are still needed to further explore the applicability of the PHQ-8 as a suicide risk assessment tool among the FCs of other patient populations in Nigeria and Sub-Sahara Africa. In conclusion, we have demonstrated that the PHQ-8 has satisfactory validity and usefulness as a suicide risk assessment tool among the Nigerian FCs of patients with depressive disorders.
| Conclusions|| |
We have demonstrated that the PHQ-8 has satisfactory validity, validity, and usefulness as a suicide risk assessment tool among the Nigerian FCs of patients with psychiatric disorders.
We sincerely want to show our gratitude to all the family caregivers and patients in the two university teaching hospitals mental health clinics that agreed to participate in this study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]