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Item response theory and factor analysis as a mean to characterize occurrence of response shift in a longitudinal quality of life study in breast cancer patients.

Anota A, Bascoul-Mollevi C, Conroy T, Guillemin F, Velten M, Jolly D, Mercier M, Causeret S, Cuisenier J, Graesslin O, Hamidou Z, Bonnetain F - Health Qual Life Outcomes (2014)

Bottom Line: At six months, the recalibration effect was statistically significant for 11/22 dimensions of the QLQ-C30 and BR23 according to the LLRA model (p ≤ 0.001).Our findings demonstrate the usefulness of these analyses in characterizing the occurrence of RS.PCA is an indirect method in investigating the reprioritization and reconceptualization components of RS.

View Article: PubMed Central - HTML - PubMed

Affiliation: Quality of Life in Oncology Platform, Besançon, France. aanota@chu-besancon.fr.

ABSTRACT

Background: The occurrence of response shift (RS) in longitudinal health-related quality of life (HRQoL) studies, reflecting patient adaptation to disease, has already been demonstrated. Several methods have been developed to detect the three different types of response shift (RS), i.e. recalibration RS, 2) reprioritization RS, and 3) reconceptualization RS. We investigated two complementary methods that characterize the occurrence of RS: factor analysis, comprising Principal Component Analysis (PCA) and Multiple Correspondence Analysis (MCA), and a method of Item Response Theory (IRT).

Methods: Breast cancer patients (n = 381) completed the EORTC QLQ-C30 and EORTC QLQ-BR23 questionnaires at baseline, immediately following surgery, and three and six months after surgery, according to the "then-test/post-test" design. Recalibration was explored using MCA and a model of IRT, called the Linear Logistic Model with Relaxed Assumptions (LLRA) using the then-test method. Principal Component Analysis (PCA) was used to explore reconceptualization and reprioritization.

Results: MCA highlighted the main profiles of recalibration: patients with high HRQoL level report a slightly worse HRQoL level retrospectively and vice versa. The LLRA model indicated a downward or upward recalibration for each dimension. At six months, the recalibration effect was statistically significant for 11/22 dimensions of the QLQ-C30 and BR23 according to the LLRA model (p ≤ 0.001). Regarding the QLQ-C30, PCA indicated a reprioritization of symptom scales and reconceptualization via an increased correlation between functional scales.

Conclusions: Our findings demonstrate the usefulness of these analyses in characterizing the occurrence of RS. MCA and IRT model had convergent results with then-test method to characterize recalibration component of RS. PCA is an indirect method in investigating the reprioritization and reconceptualization components of RS.

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Related in: MedlinePlus

Graph representing the correlation between QLQ-C30 scores and the first two principal components of Principal Component Analysis at each prospective measurement time (N = 192): at baseline (Panel A), just after surgery (Panel B), at three months (Panel C) and at six months (Panel D). The QLQ-C30 measures five functional scales (physical functioning (pf), role functioning (rf), emotional functioning (ef), cognitive functioning (cf), social functioning (sf)), global health status (GHS), financial difficulties (Fi) and eight symptom scales (fatigue (fa), nausea and vomiting (na), pain (pa), dyspnea (dy), insomnia (in), appetite loss (A), constipation (CO), diarrhea (Dia)).
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Figure 2: Graph representing the correlation between QLQ-C30 scores and the first two principal components of Principal Component Analysis at each prospective measurement time (N = 192): at baseline (Panel A), just after surgery (Panel B), at three months (Panel C) and at six months (Panel D). The QLQ-C30 measures five functional scales (physical functioning (pf), role functioning (rf), emotional functioning (ef), cognitive functioning (cf), social functioning (sf)), global health status (GHS), financial difficulties (Fi) and eight symptom scales (fatigue (fa), nausea and vomiting (na), pain (pa), dyspnea (dy), insomnia (in), appetite loss (A), constipation (CO), diarrhea (Dia)).

Mentions: Concerning the QLQ-C30 (Figure 2), functional scales became more interrelated and related to the first principal component, reflecting a strong positive correlation between these scales (Table 7). This is observed at each measurement time point. Fatigue and pain remained strongly correlated at each measurement time point, a little less at M3. Diarrhea and financial difficulties were correlated just after surgery (Figure 2B). Nausea and vomiting were correlated to appetite loss at M6 (Figure 2D).


Item response theory and factor analysis as a mean to characterize occurrence of response shift in a longitudinal quality of life study in breast cancer patients.

Anota A, Bascoul-Mollevi C, Conroy T, Guillemin F, Velten M, Jolly D, Mercier M, Causeret S, Cuisenier J, Graesslin O, Hamidou Z, Bonnetain F - Health Qual Life Outcomes (2014)

Graph representing the correlation between QLQ-C30 scores and the first two principal components of Principal Component Analysis at each prospective measurement time (N = 192): at baseline (Panel A), just after surgery (Panel B), at three months (Panel C) and at six months (Panel D). The QLQ-C30 measures five functional scales (physical functioning (pf), role functioning (rf), emotional functioning (ef), cognitive functioning (cf), social functioning (sf)), global health status (GHS), financial difficulties (Fi) and eight symptom scales (fatigue (fa), nausea and vomiting (na), pain (pa), dyspnea (dy), insomnia (in), appetite loss (A), constipation (CO), diarrhea (Dia)).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4016038&req=5

Figure 2: Graph representing the correlation between QLQ-C30 scores and the first two principal components of Principal Component Analysis at each prospective measurement time (N = 192): at baseline (Panel A), just after surgery (Panel B), at three months (Panel C) and at six months (Panel D). The QLQ-C30 measures five functional scales (physical functioning (pf), role functioning (rf), emotional functioning (ef), cognitive functioning (cf), social functioning (sf)), global health status (GHS), financial difficulties (Fi) and eight symptom scales (fatigue (fa), nausea and vomiting (na), pain (pa), dyspnea (dy), insomnia (in), appetite loss (A), constipation (CO), diarrhea (Dia)).
Mentions: Concerning the QLQ-C30 (Figure 2), functional scales became more interrelated and related to the first principal component, reflecting a strong positive correlation between these scales (Table 7). This is observed at each measurement time point. Fatigue and pain remained strongly correlated at each measurement time point, a little less at M3. Diarrhea and financial difficulties were correlated just after surgery (Figure 2B). Nausea and vomiting were correlated to appetite loss at M6 (Figure 2D).

Bottom Line: At six months, the recalibration effect was statistically significant for 11/22 dimensions of the QLQ-C30 and BR23 according to the LLRA model (p ≤ 0.001).Our findings demonstrate the usefulness of these analyses in characterizing the occurrence of RS.PCA is an indirect method in investigating the reprioritization and reconceptualization components of RS.

View Article: PubMed Central - HTML - PubMed

Affiliation: Quality of Life in Oncology Platform, Besançon, France. aanota@chu-besancon.fr.

ABSTRACT

Background: The occurrence of response shift (RS) in longitudinal health-related quality of life (HRQoL) studies, reflecting patient adaptation to disease, has already been demonstrated. Several methods have been developed to detect the three different types of response shift (RS), i.e. recalibration RS, 2) reprioritization RS, and 3) reconceptualization RS. We investigated two complementary methods that characterize the occurrence of RS: factor analysis, comprising Principal Component Analysis (PCA) and Multiple Correspondence Analysis (MCA), and a method of Item Response Theory (IRT).

Methods: Breast cancer patients (n = 381) completed the EORTC QLQ-C30 and EORTC QLQ-BR23 questionnaires at baseline, immediately following surgery, and three and six months after surgery, according to the "then-test/post-test" design. Recalibration was explored using MCA and a model of IRT, called the Linear Logistic Model with Relaxed Assumptions (LLRA) using the then-test method. Principal Component Analysis (PCA) was used to explore reconceptualization and reprioritization.

Results: MCA highlighted the main profiles of recalibration: patients with high HRQoL level report a slightly worse HRQoL level retrospectively and vice versa. The LLRA model indicated a downward or upward recalibration for each dimension. At six months, the recalibration effect was statistically significant for 11/22 dimensions of the QLQ-C30 and BR23 according to the LLRA model (p ≤ 0.001). Regarding the QLQ-C30, PCA indicated a reprioritization of symptom scales and reconceptualization via an increased correlation between functional scales.

Conclusions: Our findings demonstrate the usefulness of these analyses in characterizing the occurrence of RS. MCA and IRT model had convergent results with then-test method to characterize recalibration component of RS. PCA is an indirect method in investigating the reprioritization and reconceptualization components of RS.

Show MeSH
Related in: MedlinePlus