Browsing by Subject "factor analysis"
Now showing 1 - 4 of 4
Results Per Page
Sort Options
Item Open Access A factor analysis of posttraumatic stress disorder symptoms using data pooled from two venlafaxine extended-release clinical trials.(Brain Behav, 2013-11) Stein, Dan J; Rothbaum, Barbara O; Baldwin, David S; Szumski, Annette; Pedersen, Ronald; Davidson, Jonathan RTBACKGROUND: Confirmatory factor analysis (CFA) of Diagnostic and Statistical Manual of Mental Disorders (Fourth Edition) (DSM-IV) three-factor posttraumatic stress disorder (PTSD) diagnostic criteria was conducted to determine fit for this patient population. An exploratory factor analysis (EFA) of alternate symptom structures was planned to identify symptoms that cluster in this population. The response of symptom factors to treatment with venlafaxine extended release (ER) was explored. METHODS: Baseline 17-item Clinician-Administered PTSD Scale (CAPS-SX17) data were pooled from patients enrolled in two double-blind, randomized, placebo-controlled trials. The CFA was conducted using maximum likelihood and weighted, least-squares factor extraction methods. The EFA was performed using a polychoric correlation covariance matrix and Pearson correlation matrix. RESULTS: Data from a pooled population of 685 patients (venlafaxine ER: n = 339; placebo: n = 346) were analyzed. CFA rejected the DSM-IV three-factor structure. The EFA identified a different three-factor structure as the best fit: factor 1 included reexperiencing symptoms, factor 2 included symptoms of altered mood and cognition, whereas factor 3 comprised avoidance and arousal symptoms. All DSM-IV symptom factors and all factors in the identified three-factor model responded positively to venlafaxine ER treatment. CONCLUSIONS: Data are consistent with literature failing to confirm the three-factor structure of DSM-IV PTSD, and they support the DSM-5 inclusion of a symptom cluster addressing altered mood and cognition in PTSD. The efficacy of venlafaxine ER in reducing a range of symptom clusters in PTSD is consistent with its multiple mechanisms of action.Item Open Access It Is as It Was: MDS-UPDRS Part III Scores Cannot Be Combined with Other Parts to Give a Valid Sum.(Movement disorders : official journal of the Movement Disorder Society, 2022-12) Goetz, Christopher G; Choi, Dongrak; Guo, Yuanyuan; Stebbins, Glenn T; Mestre, Tiago A; Luo, ShengBackground
Original clinimetric analyses by the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS) developers did not confirm the validity of summing the scores of its parts. Recent studies used the summed score of Part III and other parts as efficacy outcomes.Objective
The aim of this study was to establish whether summing scores of MDS-UPDRS parts can be recommended.Methods
Using 7466 full MDS-UPDRS scores, we applied two-step factor analysis as in the original article to reassess the validity analysis with the threshold criterion set at comparative fit index ≥0.9.Results
All comparative fit indexes of any combination including Part III were lower than 0.90.Conclusions
Summing Part III MDS-UPDRS scores with other parts is not clinimetrically sound. The MDS-UPDRS is a validated four-part scale with corresponding individual part scores and needs to be used within the limits originally presented. © 2022 International Parkinson and Movement Disorder Society.Item Open Access Reply to: Comment on "Summing MDS-UPDRS Parts 1 + 2 (Non-motor and Motor Experience of Daily Living): The Patient's Voice".(Movement disorders : official journal of the Movement Disorder Society, 2023-08) Goetz, Christopher G; Zou, Haotian; Stebbins, Glenn T; Schrag, Anette; Mestre, Tiago A; Luo, ShengItem Open Access Summing MDS-UPDRS Parts 1 + 2 (Non-motor and Motor Experience of Daily Living): The Patient's Voice.(Movement disorders : official journal of the Movement Disorder Society, 2023-04) Zou, Haotian; Goetz, Christopher G; Stebbins, Glenn T; Schrag, Anette; Mestre, Tiago A; Luo, Sheng