Measurement error in the Liebowitz Social Anxiety Scale: results from a general adult population in Japan

Assessing the Smallest Detectable Change of the Kessler Psychological Distress Scale Score in an Adult Population in Japan

Background

Psychological distress is prevalent worldwide and can lead to the development of mental conditions such as major depression and anxiety disorders. It is essential to assess the severity of patient-reported outcomes to provide effective treatment for psychological distress. The Kessler Psychological Distress Scale (K6) is one of the most widely used psychological distress scales. However, the smallest detectable change (SDC) of the K6 score has not been elucidated. Therefore, the current study aimed to determine the SDC of the K6 score in a Japanese adult population.

Methods

Participants aged 20-59 years who are native Japanese speakers were recruited from the panel list of a web research firm. The K6 score was assessed at baseline (T1) and at 2-week follow-up (T2). SDCs were calculated at the individual (SDC_ind) and group (SDC_group) levels. Intraclass correlation coefficient agreement (ICC_agreement) was calculated to assess test-retest reliability and Cronbach's alpha to evaluate internal consistency.

Results

A total of 3254 (1627 [50%] female) responded at T1 and T2. The mean (standard deviation) K6 scores were 5.71 (5.84) at T1 and 5.65 (5.83) at T2. The SDC_ind and SDC_group of the K6 score were 8.47 (35.31%) and 0.15 (0.63%), respectively. The ICC_agreement was 0.73, and the Cronbach's alpha was 0.94.

Conclusion

Our study provided evidence on the reliability and interpretation of the K6 score. Calculating the SDC of the K6 score can help identify the significance of changes in psychological distress over time and can determine the efficacy of interventions for psychological distress.

The Prevalence and Sociodemographic Correlates of Social Anxiety Disorder: A Focused National Survey

Background

Social Anxiety Disorder (SAD) is among the most common anxiety disorders worldwide with data largely emerging from the Euro-American and Pacific Rim populations. In contrast, there is a dearth of studies among the populations of Arabian Gulf countries including Oman. This study has two interrelated aims: (i) to explore the prevalence of SAD among Omani adults, and (ii) to tease out the links between socio-demographic factors and SAD in Oman.

Methods

A cross-sectional study via an online survey was conducted among 1019 adult Omani nationals residing in Oman. The presence of SAD was assessed using the Arabic version of the Liebowitz Social Anxiety Scale (LSAS).

Results

Nearly half the participants (45.9%, n = 468) exhibited “caseness” for SAD as defined by LSAS. In the multivariate logistic analysis, participants below 40 years of age were 1.6 times (OR = 1.568, p = .026) more likely to have caseness for SAD than those who were 40 and older. Women were 1.3 times (OR = 1.348, p = .038) more likely to exhibit caseness for SAD than men. Participants who had secondary or undergraduate education were respectively 1.5 times (OR = 1.45, p = .014) and 2.5 times (OR = 2.509, p < .001) to have caseness for SAD than those who were graduates.

Conclusion

The present data suggest that 45.9% of the participants reached the cut-off for caseness in LSAS, which is high compared to reports from other populations. The present accrued frequency is discussed within the context of the accrued response rate, socio-cultural factors as well as the tendency for self-reported measures to “produce” spurious results is also highlighted which, in turn, calls for studies that adopt more inclusive survey methods.

Development of Deployable Predictive Models for Minimal Clinically Important Difference Achievement Across the Commonly Used Health-related Quality of Life Instruments in Adult Spinal Deformity Surgery

STUDY DESIGN

Retrospective analysis of prospectively-collected, multicenter adult spinal deformity (ASD) databases.

OBJECTIVE

To predict the likelihood of reaching minimum clinically important differences in patient-reported outcomes after ASD surgery.

SUMMARY OF BACKGROUND DATA

ASD surgeries are costly procedures that do not always provide the desired benefit. In some series only 50% of patients achieve minimum clinically important differences in patient-reported outcomes (PROs). Predictive modeling may be useful in shared-decision making and surgical planning processes. The goal of this study was to model the probability of achieving minimum clinically important differences change in PROs at 1 and 2 years after surgery.

METHODS

Two prospective observational ASD cohorts were queried. Patients with Scoliosis Research Society-22, Oswestry Disability Index , and Short Form-36 data at preoperative baseline and at 1 and 2 years after surgery were included. Seventy-five variables were used in the training of the models including demographics, baseline PROs, and modifiable surgical parameters. Eight predictive algorithms were trained at four-time horizons: preoperative or postoperative baseline to 1 year and preoperative or postoperative baseline to 2 years. External validation was accomplished via an 80%/20% random split. Five-fold cross validation within the training sample was performed. Precision was measured as the mean average error (MAE) and R values.

RESULTS

Five hundred seventy patients were included in the analysis. Models with the lowest MAE were selected; R values ranged from 20% to 45% and MAE ranged from 8% to 15% depending upon the predicted outcome. Patients with worse preoperative baseline PROs achieved the greatest mean improvements. Surgeon and site were not important components of the models, explaining little variance in the predicted 1- and 2-year PROs.

CONCLUSION

We present an accurate and consistent way of predicting the probability for achieving clinically relevant improvement after ASD surgery in the largest-to-date prospective operative multicenter cohort with 2-year follow-up. This study has significant clinical implications for shared decision making, surgical planning, and postoperative counseling.

LEVEL OF EVIDENCE

4.