Logistic Mixed Model Analysis Research Articles

Decrease of 7T MR short-term effects with repeated exposure

PurposeAlthough participants in 7 T magnetic resonance (MR) studies tolerate ultra-high field (UHF) well, subjectively experienced short-term effects, such as dizziness, inconsistent movement, nausea, or metallic taste, are reported. Evidence on subjectively experienced short-term effects in multiple exposures to UHF MR is scarce. The purpose of this study is to investigated experience of short-term effects, and occurrence of motion in healthy subjects exposed to seven weekly 7 T MR examinations.MethodsA questionnaire on short-term effects was completed by participants in an fMRI motor skill study. Seven UHF MR examinations were conducted over 7 weeks (exposure number: 1 to 7). Changes of experienced short-term effects were analyzed. Motion in fMRI images was quantified.ResultsThe questionnaire was completed 360 times by 67 participants after one to seven 7T MR examinations. Logistic mixed model analysis showed a significant association between dizziness, inconsistent movement, nausea, and headache and the examination numbers (p<0.03). Exposure to repeated examinations had no significant effect on peripheral nerve stimulation (PNS) or motion of the subjects. The overall experience of a 7T examination improved significantly (p<0.001) with increasing examination numbers.ConclusionDuring multiple 7T examinations, subjects adapt to the strong static field. The short-term effects dizziness, inconsistent movement, nausea, and headache decrease over time as the MR sessions continue and experienced comfort increases. There was no significant difference in motion during the multiple fMRI examinations.

Risk Factors for Readmission After Pulmonary Lobectomy: A Quality Collaborative Study

BackgroundPrevious studies have identified postoperative complications as being associated with readmission after lobectomy. However, these studies have not adequately accounted for the timing of complications or accounted for institutional effects. Our objectives were to examine readmission rates after lobectomy and identify factors associated with readmission. MethodsPatients aged >18 years undergoing lobectomy for lung cancer between 2015 and 2019 were identified from a statewide database. Patients with in-hospital mortality, missing data regarding discharge status, 30-day readmission status, and discharge location were excluded. Data regarding The Society of Thoracic Surgeons postoperative complications were abstracted by hospital data managers to determine the timing of occurrence (index admission vs readmission). Logistic mixed-model analysis, with hospitals as the random intercept to account for clustering data structure and assess hospital-specific effect on readmission, was performed. ResultsThe overall readmission rate was 6.9% (184 of 2686). The most common complication was air leak ≥5 days in 17.4% (467 of 2686). Variables significantly predictive of more readmission were predischarge postoperative complications and Zubrod score ≥1. Variables predictive of less readmission were increasing length of stay and having been operated on at institutions with higher cumulative volume or having postdischarge follow-up visit protocol ≤7 days from discharge. The C statistic for the final model was 0.80. ConclusionsPatients who experience postoperative complications are at increased risk for readmission, whereas follow-up ≤7 days was predictive of less risk for readmission. Efforts at reducing readmissions should focus on decreasing postoperative complication rates, the timing of discharge for patients experiencing complications, as well as decreasing length of time between discharge and clinic follow-up.

The Use of the LITMUS Quasi-Universal Nonword Repetition Task to Identify DLD in Monolingual and Early Second Language Learners Aged 8 to 10

This study evaluates whether the short version of the German LITMUS quasi-universal nonword repetition task (LITMUS-QU-NWR) can be used as an index test for monolingual and early second language learners (eL2) of German aged 8 to 10 years. The NWR taps into quasi-universal phonological knowledge via the so-called language-independent part and into language-specific phonological knowledge via the language-dependent part. Thirty-six monolingual and thirty-three eL2 learners of German, typically developing (TD) and diagnosed as language-impaired (DLD), participated in the study. The effects of the language group (Mo vs. eL2) and the clinical status (TD vs. DLD) on repetition accuracy are investigated by a logistic mixed-model analysis. Receiver operating characteristics (ROC) and likelihood ratios are calculated to determine the diagnostic accuracy of the two parts. The group comparisons showed significant effects of the clinical status but not of the language group. The ROC analyses and the likelihood ratios reveal better diagnostic values for the language-dependent compared to the language-independent part and almost similar diagnostic values for the monolingual and the eL2 group. The results indicate that the LITMUS-QU-NWR helps to disentangle DLD and DLD in monolingual children and eL2 learners aged 8 to 10 years.

Change over time: the use of seclusion in secure residential youth care in The Netherlands

ABSTRACT Seclusion can be harmful for children and adolescents. Hence, all locations for secure residential youth care in the Netherlands are committed to reduce its use by implementing monitoring and feedback as a seclusion reduction intervention. This study examined change over time in the use of seclusion in secure residential youth care in the Netherlands using a broad conceptualization of seclusion and by analyzing four variables (frequency, duration, room, reason). During two six months periods, seclusions were registered in 19 locations. Every month, all locations received feedback on the use of seclusion. Negative binomial mixed model analyses were used to investigate change over time in frequency and duration of seclusion. Logistic mixed model analyses were used to identify change over time in reason for use and type of room used for seclusion. Results showed that seclusion frequency significantly decreased (RR = 0.92, p < .001). Further, duration of placement in a seclusion room significantly increased (RR = 1.04, p < .001). This change was only significant in seclusion in response to aggression (RR = 1.06, p < .001). The results emphasize the need for future studies to examine reduction using a broad conceptualization of seclusion.

Hyperreflective material serves as a potential biomarker of dyslipidemia in diabetic macular edema

PurposeThe aim of this study was to investigate the vision-affected optical coherence tomography (angiography) (OCT/OCTA)-based morphological characteristics of diabetic macular edema (DME) and to explain their possible underlying mechanisms from a systemic perspective. MethodsDiabetic patients with DME were included in this retrospective study. The clinical profiles and OCT/OCTA morphological characteristics were recorded. Linear mixed-model analyses were performed between best-corrected visual acuity (BCVA) and each OCT/OCTA morphological characteristic. Linear and logistic mixed-model analyses were performed between each vision-affected morphological characteristic and the clinical characteristics. ResultsEighty-five eyes of 85 patients were included. The number of hyperreflective dots (HDs) (p<0.001) and hyperreflective foci (HF) (p = 0.006) was positively correlated with LogMAR BCVA in the univariate analysis. The number of HDs (p = 0.008) remained correlated with LogMAR BCVA in the multivariate analysis. Eyes with an increased number of HF (p = 0.01) were more likely to have hard exudates within a fovea area diameter of 3 mm, while the relationship between the number of HDs and the presence of hard exudates did not reach significance. In the multivariate analysis, the increased level of total cholesterol (TC) (p = 0.004) and the reduced level of serum albumin (p = 0.014) were associated with an increased number of HDs, and the level of serum TC (p = 0.039) was positively associated with the number of HF. ConclusionHyperreflective material may be a predictor for BCVA and serves as a potential biomarker of dyslipidemia in DME. It was postulated that HF are mainly related to hard exudates and HDs are partially associated with microglial cell activation.

Should we use logistic mixed model analysis for the effect estimation in a longitudinal RCT with a dichotomous outcome variable?

Background: Within epidemiology both mixed model analysis and Generalised Estimating Equations (GEE analysis) are frequently used to analyse longitudinal RCT data. With a continuous outcome, both methods lead to more or less the same results, but with a dichotomous outcome the results are totally different. The purpose of the present study is to evaluate the performance of a logistic mixed model analysis and a logistic GEE analysis and to give an advice which of the two methods should be used.&#x0D; Methods: Two real life RCT datasets with and without missing data were used to perform this evaluation. Regarding the logistic mixed model analysis also two different estimation procedures were compared to each other.&#x0D; Results: The regression coefficients obtained from the two logistic mixed model analyses were different from each other, but were always higher then the regression coefficients derived from a logistic GEE analysis. Because this also holds for the standard errors, the corresponding p-values were more or less the same. It was further shown that the effect estimates derived from a logistic mixed model analysis were an overestimation of the ‘real’ effect estimates.&#x0D; Conclusions: Although logistic mixed model analysis is widely used for the analysis of longitudinal RCT data, this article shows that logistic mixed model analysis should not be used when one is interested in the magnitude of the regression coefficients (i.e. effect estimates).

Andexanet Alfa or Prothrombin Complex Concentrate for Factor Xa Inhibitor Reversal in Acute Major Bleeding: A Systematic Review and Meta-Analysis.

To combine evidence on andexanet alfa and prothrombin complex concentrates for factor Xa inhibitor-associated bleeding to guide clinicians on reversal strategies. Embase, Pubmed, Web of Science, and the Cochrane Library. Observational studies and randomized clinical trials studying hemostatic effectiveness of andexanet alfa or prothrombin complex concentrate for acute reversal of factor Xa inhibitor-associated hemorrhage. Two independent reviewers extracted the data from the studies. Visualization and comparison of hemostatic effectiveness using Sarode et al or International Society of Thrombosis and Hemostasis Scientific and Standardization Committee criteria at 12 and 24 hours, (venous) thrombotic event rates, and inhospital mortality were performed by constructing Forest plots. Exploratory analysis using a logistic mixed model analysis was performed to identify factors associated with effectiveness and venous thromboembolic event. A total of 21 studies were included (andexanet: 438 patients; prothrombin complex concentrate: 1,278 patients). The (weighted) mean effectiveness for andexanet alfa was 82% at 12 hours and 71% at 24 hours. The (weighted) mean effectiveness for prothrombin complex concentrate was 88% at 12 hours and 76% at 24 hours. The mean 30-day symptomatic venous thromboembolic event rates were 5.0% for andexanet alfa and 1.9% for prothrombin complex concentrate. The mean 30-day total thrombotic event rates for andexanet alfa and prothrombin complex concentrate were 10.7% and 3.1%, respectively. Mean inhospital mortality was 23.3% for andexanet versus 15.8% for prothrombin complex concentrate. Exploratory analysis controlling for potential confounders did not demonstrate significant differences between both reversal agents. Currently, available evidence does not unequivocally support the clinical effectiveness of andexanet alfa or prothrombin complex concentrate to reverse factor Xa inhibitor-associated acute major bleeding, nor does it permit conventional meta-analysis of potential superiority. Neither reversal agent was significantly associated with increased effectiveness or a higher rate of venous thromboembolic event. These results underscore the importance of randomized controlled trials comparing the two reversal agents and may provide guidance in designing institutional guidelines.

Antibody Development and Disease Severity of Covid-19 in Non-Immunized Patients with Rheumatic Immune-Mediated Inflammatory Diseases: Data from a Prospective Cohort Study

Background: Research on the disease severity of COVID-19 in patients with rheumatic immune-mediated inflammatory diseases (IMIDs) has been inconclusive, and long-term prospective data on the development of SARS-CoV-2 antibodies in these patients are lacking. We conducted an investigator-driven prospective cohort study to compare the disease severity of COVID-19, and the development of SARS-CoV-2 antibodies over time between patients with rheumatic IMIDs and healthy controls.Methods: Adult patients with rheumatic IMIDs from the Amsterdam Rheumatology & immunology Center, Amsterdam were invited to participate. All patients were asked to recruit their own sex- and age-matched control subject. We developed a new platform for collecting clinical data in large patient groups with online questionnaires (at baseline, and after 1-4 and 5-9 months of follow-up). Serum samples were collected two times during follow-up; after completing the follow-up questionnaires and prior to COVID-19 vaccination. All serum samples were analyzed for the presence of SARS-CoV-2 specific antibodies with a total-antibody bridging ELISA. IgG titers were quantified in samples with a positive test result in the bridging assay. Logistic regression analyses, and linear and logistic mixed model analyses were used to compare COVID-19 related hospitalization rates, proportions of SARS-CoV-2 seropositivity and IgG antibody titers between patients and controls, and between patients stratified for major immunosuppressive drug categories (i.e. biological [b] or conventional synthetic [cs] disease modifying anti-rheumatic drugs [DMARDs]).Findings: In total, 3080 consecutive patients and 1102 healthy controls with comparable age and sex distribution were included for analyses. The incidence of COVID-19 was slightly lower in patients compared to controls (14.7% vs. 16.0% had detectable SARS-CoV-2 antibodies), but patients were more frequently hospitalized compared to controls; 23 of 347 (7%) patients vs. 1 of 134 (0.7%) controls (adjusted OR: 7.33, 95% CI: 0.96 – 55.77, P 0.055). Three (13%) of 23 patients were admitted to the intensive care unit (ICU), and one of these died. Only treatment with B-cell targeting therapy was independently associated with an increased risk of COVID-19 related hospitalization (adjusted OR: 14.62, 95% CI: 2.31 – 92.39, P 0.004). Proportions of SARS-CoV-2 seropositivity in participants with a PCR confirmed COVID-19 diagnosis were similar for patients and controls ( P 0.73), and did not significantly decrease during the first twelve months after infection ( P 0.10). IgG antibody titers were higher in hospitalized patients compared to non-hospitalized patients, and slowly declined with time (rate per month: 0.86, 95% CI: 0.81 – 0.91, P Interpretation: We observed that patients with rheumatic IMIDs, especially those treated with B-cell targeting therapy, were more likely to be hospitalized when infected with SARS-CoV-2, although subsequent ICU admissions and/or death were infrequent. In addition, treatment with cs- or bDMARDs other than B-cell targeting agents is unlikely to have negative effects on the development of long-lasting humoral immunity against SARS-CoV-2.Funding Information: ZonMw and Reade Foundation.Declaration of Interests: None to declare. Ethics Approval Statement: The research protocol was approved by the medical ethical committee of the VU University medical center (registration number 2020.169). All participants gave written informed consent.

Effects of Hatchery Rearing Density, Handling, and Nutrition on Renibacterium salmoninarum Infection Prevalence in Juvenile Chinook Salmon.

Bacterial kidney disease, caused by Renibacterium salmoninarum (RS), is a chronic and often fatal disease of salmonid species, and can be particularly harmful to hatchery-reared Chinook Salmon Oncorhynchus tshawytscha. A considerable amount of research has focused on the prevention of vertical and horizontal transmission; however, a comparatively little amount has investigated factors that increase the prevalence of RS infection in captive environments. We evaluated the effects of three common hatchery conditions (handling, nutrition level, and rearing density) on RS infection prevalence. Fish were sampled at 30-d and 60-d postexposure to RS. Of 577 juveniles examined, 65 (11.27%) had anterior kidneys infected with RS. Using a logistic mixed model analysis, we found effects of nutrition level (P=0.018), handling (P=0.010), and sampling period (P=0.003) on the prevalence of RS. The interactions of nutrition and handling (P=0.008) and nutrition and time (P<0.001) were also significant. When fed a standard-nutrition diet, proportionately fewer fish were infected with RS when not handled (7.16% versus 0.04%; P=0.003). Fish in the standard-nutrition group also had a lower prevalence of RS during the second sampling period (4.08% versus 0.08%, respectively; P<0.001). When not handled, rearing with standard nutrition (11.50% versus 0.04%; P=0.004) resulted in a reduction in prevalence of RS infection. Additionally, nonhandled fish had a much lower prevalence of RS infection during the second sampling period (2.66% versus 0.21%; P=0.009). While density did not affect the prevalence of RS infection (P=0.145), fish reared at a higher density had lower RS infection when not handled (16.48% versus 0.84%, P=0.004). For fish at a higher density, the RS prevalence was lower during the second sampling period (10.57% versus 1.40%; P=0.002). Our results suggest that hatchery managers can reduce RS infection prevalence by maintaining an adequate nutritional regime as recommended by the manufacturer. Additionally, the prevalence of RS may be reduced if managers decrease handling of hatchery-reared Chinook Salmon if exposed to RS.

A single assessment with the Brief Adherence Rating Scale (BARS) discriminates responders to long-acting injectable antipsychotic treatment in patients with schizophrenia

ObjectiveTo determine if a single baseline adherence assessment (Brief Adherence Rating Scale [BARS]) could identify patients who are likely to respond to long-acting injectable (LAI) antipsychotic treatment. MethodThe current secondary analysis included a sub-sample of adult outpatients (N = 176) with schizophrenia or schizoaffective disorder who participated in the “A Comparison of Long-Acting Injectable Medications for Schizophrenia (ACLAIMS)” trial and had a baseline BARS assessment and a baseline and month 3 Positive and Negative Syndrome Scale (PANSS) rating. The main outcome was LAI treatment response, defined as a ≥ 20% decrease (baseline to month 3) on the PANSS total score. Receiver Operating Characteristic (ROC) and Area Under the Curve (AUC) analysis was conducted to determine the optimal cutpoint of baseline BARS adherence in discriminating LAI treatment response at month 3. A logistic mixed model estimated the odds of response to LAI treatment at month 3 from the optimal baseline BARS cutpoint. ResultsThe ROC analysis determined that the single baseline BARS rating (cutoff ≤66%), indicating low adherence, best discriminated patients likely to respond to LAI treatment (AUC = 0.603, SE = 0.046, 95% binomial exact CI = 0.527 to 0.676, p = 0.025), with 38% sensitivity and 85% specificity. The logistic mixed model analysis revealed that patients with ≤66% BARS adherence had 3.464 times the predicted odds (95% CI = 1.604 to 7.480, p = 0.001) of responding to LAI treatment than those who were >66% BARS adherent. ConclusionA single baseline BARS assessment discriminated response to LAI treatment suggesting it is a reasonable tool to identify candidates for LAI antipsychotic treatment.

Expectations in the Ultimatum Game: Distinct Effects of Mean and Variance of Expected Offers.

Being treated fairly by others is an important need in everyday life. Experimentally, fairness can be studied using the Ultimatum Game, where the decision to reject a low, but non-zero offer is seen as a way to punish the other player for an unacceptable offer. The canonical explanation of such behavior is inequity aversion: people prefer equal outcomes over personal gains. However, there is abundant evidence that people's decision to reject a low offer can be changed by contextual factors and their emotional state, which cannot be explained by the inequity aversion model. Here, we expand a recent alternative explanation: rejections are driven by deviations from expectations: the larger the difference between the actual offer and the expected offer, the more likely one is to reject the offer. Specifically, we provided participants with explicit information on what kind of offers to expect using histograms depicting distribution of offers given in a previous experiment by the same proposers. Crucially, we showed four different distributions, manipulating both the mean and the variance of these expected sets of offers. We found that 50% of our participants clearly and systematically changed their behavior as a function of their expectations (11% followed the standard-economic model of pure self-interest and 39% where not distinguishable from the inequity-aversion model). Using a logistic mixed-model analysis, we found that the mean and variance differently affect the decision to reject an offer. Specifically, the mean expected offer affected the threshold of what offers are acceptable, while the expected variance of offers changed how strict participants were about this threshold. Together, these results suggest that social expectations have a more complex nature as current theories propose.

Effectiveness of a lumbopelvic monitor and feedback device to change postural behaviour: a protocol for the ELF cluster randomised controlled trial

IntroductionLow back pain (LBP) is the most common, costly and disabling musculoskeletal disorder worldwide, and is prevalent in healthcare workers. Posture is a modifiable risk factor for LBP shown to...

Predicting placebo response in adolescents with major depressive disorder: The Adolescent Placebo Impact Composite Score (APICS)

ObjectiveThe aim of this study was to construct a composite scoring system to predict the probability of placebo response in adolescents with Major Depressive Disorder (MDD). MethodParticipants of the current study were 151 adolescents (aged 12–17 years) who were randomized to the placebo arm (placebo transdermal patches) of a randomized controlled trial (RCT) comparing the selegiline transdermal patch with placebo (DelBello et al., 2014). The primary outcome of response was defined as a CGI-I score of 1 or 2 (very much or much improved) at week 12 (study-end) or exit. As a first step, a multiple logistic mixed model was used to estimate the odds of placebo response from each predictor in the model, including age, CDRS-R total at baseline (depressive symptom severity), history of recurrent depression (yes vs. no), sex (female vs. male), and race (non-Caucasian vs. Caucasian). On the basis of the initial logistic mixed model analysis, we then constructed an Adolescent Placebo Impact Composite Score (APICS) that became the sole predictor in a re-specified Bayesian logistic regression model to estimate the probability of placebo response. Finally, the AUC for the APICS was tested against a nominal area of 0.50 to evaluate how well the APICS discriminated placebo response status. ResultsAmong the 151 adolescents, with a mean age of 14.6 years (SD = 1.6) and a mean baseline CDRS-R total of 60.6 (SD = 12.1), 68.2% were females, 50.3% was Caucasian, and 39.7% had a history of recurrent depression. Placebo response rate was 58.3%. Based on the logistic mixed model, the re-specified equation with the highest discriminatory ability to estimate the probability of placebo response was APICS = age + (0.32 × CDRS-R Total at baseline) + (−2.85 × if female) + (−5.50 × if history of recurrent depression) + (−5.85 × if non-Caucasian). The AUC for this model was 0.59 (p = .049). Within a Bayesian decision-theoretic framework, in 95.5% of the time, the 10,000 posterior Monte Carlo samples suggested that as APICS decreased the probability of placebo response increased. The observed APICS and related probability of responding to placebo in this adolescent sample ranged from 14.1 = 74.1% (in placebo responders) to 39.1 = 41.8% (in placebo non-responders). ConclusionThe APICS model estimates the probability of placebo response in adolescents with MDD with a modest degree of accuracy (AUC = 0.59) and with a reasonable degree of positive predictive value (74.5%), and is based on five previously identified patient characteristics of placebo response from prior meta-analytic studies (Bridge et al., 2009; Cohen et al., 2010) of randomized placebo-controlled trials of antidepressants in youth with MDD. Calculation of the APICS should be restricted to the range of the adolescent ages (12–17 years) and CDRS-R total scores (17–113); thus, the APICS can assume possible calculated values and related probability of responding to placebo ranging from about 3 (84%) to 53 (25%). The APICS Bayesian logistic model, based on a given aggregate patient profile, has a range of predicted probabilities of placebo response that is fairly wide, albeit truncated, but potentially meaningful for predicting the probability of placebo response among adolescent youth with MDD. The ability of the APICS to objectify the probability of placebo response in adolescents with MDD could be accounted for in the clinical research design of the trial itself and perhaps aid clinicians in treatment strategy for youth who are more likely to experience placebo response.

P.1.030 Mirtazapine augmentation of citalopram accelerates response in OCD patients without comorbid depression: A pilot study

The aim of this study was to construct a composite scoring system to predict the probability of placebo response in adolescents with Major Depressive Disorder (MDD).Participants of the current study were 151 adolescents (aged 12–17 years) who were randomized to the placebo arm (placebo transdermal patches) of a randomized controlled trial (RCT) comparing the selegiline transdermal patch with placebo (DelBello et al., 2014). The primary outcome of response was defined as a CGI-I score of 1 or 2 (very much or much improved) at week 12 (study-end) or exit. As a first step, a multiple logistic mixed model was used to estimate the odds of placebo response from each predictor in the model, including age, CDRS-R total at baseline (depressive symptom severity), history of recurrent depression (yes vs. no), sex (female vs. male), and race (non-Caucasian vs. Caucasian). On the basis of the initial logistic mixed model analysis, we then constructed an Adolescent Placebo Impact Composite Score (APICS) that became the sole predictor in a re-specified Bayesian logistic regression model to estimate the probability of placebo response. Finally, the AUC for the APICS was tested against a nominal area of 0.50 to evaluate how well the APICS discriminated placebo response status.Among the 151 adolescents, with a mean age of 14.6 years (SD = 1.6) and a mean baseline CDRS-R total of 60.6 (SD = 12.1), 68.2% were females, 50.3% was Caucasian, and 39.7% had a history of recurrent depression. Placebo response rate was 58.3%. Based on the logistic mixed model, the re-specified equation with the highest discriminatory ability to estimate the probability of placebo response was APICS = age + (0.32 × CDRS-R Total at baseline) + (−2.85 × if female) + (−5.50 × if history of recurrent depression) + (−5.85 × if non-Caucasian). The AUC for this model was 0.59 (p = .049). Within a Bayesian decision-theoretic framework, in 95.5% of the time, the 10,000 posterior Monte Carlo samples suggested that as APICS decreased the probability of placebo response increased. The observed APICS and related probability of responding to placebo in this adolescent sample ranged from 14.1 = 74.1% (in placebo responders) to 39.1 = 41.8% (in placebo non-responders).The APICS model estimates the probability of placebo response in adolescents with MDD with a modest degree of accuracy (AUC = 0.59) and with a reasonable degree of positive predictive value (74.5%), and is based on five previously identified patient characteristics of placebo response from prior meta-analytic studies (Bridge et al., 2009; Cohen et al., 2010) of randomized placebo-controlled trials of antidepressants in youth with MDD. Calculation of the APICS should be restricted to the range of the adolescent ages (12–17 years) and CDRS-R total scores (17–113); thus, the APICS can assume possible calculated values and related probability of responding to placebo ranging from about 3 (84%) to 53 (25%). The APICS Bayesian logistic model, based on a given aggregate patient profile, has a range of predicted probabilities of placebo response that is fairly wide, albeit truncated, but potentially meaningful for predicting the probability of placebo response among adolescent youth with MDD. The ability of the APICS to objectify the probability of placebo response in adolescents with MDD could be accounted for in the clinical research design of the trial itself and perhaps aid clinicians in treatment strategy for youth who are more likely to experience placebo response.