Top ten errors of statistical analysis in observational studies for cancer research

Carmona-Bayonas, Alberto; Jiménez-Fonseca, Paula; Fernández-Somoano, Ana; Alvarez-Manceñido, Felipe; Castañón, Eduardo; Custodio, Ana; Peña, Francisco Ayala de la; Martín-Payo, Rubén; Valiente, Luis

doi:10.1007/s12094-017-1817-9

Cited by 21 publications

(17 citation statements)

References 69 publications

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“…There were also several limitations. First, the study is based on a Clinical Register and, despite meticulous registration, data are always limited to the quality and quantity of the same34—that is, data on recurrence-free survival were not complete. Second, S-phase fraction, DNA ploidy, and p53 were analyzed on paraffin-embedded and/or fresh frozen hysterectomy and/or curettage specimens, and we could not discriminate between the proportion of hysterectomy versus curettage in the register.…”

Section: Discussionmentioning

confidence: 99%

DNA ploidy status, S-phase fraction, and p53 are not independent prognostic factors for survival in endometrioid endometrial carcinoma FIGO stage I–III

Svanvik

Strömberg

Holmberg

et al. 2019

Int J Gynecol Cancer

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ObjectivesTo assess the effects on relative survival of established and new prognostic factors in stage I–III grade 1–3 endometrioid endometrial carcinoma and in the subgroup of stage I grade 1–2.MethodsThis was a population-based, retrospective study including all women (n=1113) in the western Swedish healthcare region diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage I–III grade 1–3 endometrioid endometrial carcinoma in 2006–2011. Histology, grade, stage, and age were prospectively reported to the regional clinical and national cancer registers. DNA ploidy and S-phase fraction were analyzed by flow cytometer. S-phase fraction cut-off was set at ≥8%. Tumor biopsies were classified as diploid if there was one G0/G1 peak or the DNA index was 1.0±0.04. Overexpression of p53 as determined by immunohistochemistry was positive if strong nuclear staining was found in >30% of the neoplastic cells.ResultsBased on univariable statistical analyses we found that 5-year relative survival was significantly associated with S-phase fraction, DNA ploidy, p53, stage, grade, and age. Excess mortality for S-phase fraction ≥8%, aneuploidy, and p53 overexpression was 8, 14, and 8 and times higher, respectively. However, in a multivariable regression model, adjusted for stage, grade, and age, S-phase fraction, DNA ploidy, and p53 were not statistically independent prognostic factors (p=0.413, p=0.107, p=0.208, respectively) for 5-year relative survival in stage I–III grade 1–3 endometrioid endometrial carcinoma. In a subgroup analysis of stage I grade 1–2, aneuploidy identified a subgroup with impaired 5-year relative survival.ConclusionWe can conclude that S-phase fraction, DNA ploidy, and p53 overexpression did not improve identification of high-risk patients by stage, grade, and age in stage I–III endometrioid endometrial carcinoma. In stage I, aneuploidy and grade 2 predicted lower relative survival rates than other variables.

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Section: Discussionmentioning

confidence: 99%

DNA ploidy status, S-phase fraction, and p53 are not independent prognostic factors for survival in endometrioid endometrial carcinoma FIGO stage I–III

Svanvik

Strömberg

Holmberg

et al. 2019

Int J Gynecol Cancer

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“…Cancer characteristics, sociodemographics, health status, and behaviors, available in both cohorts at each analytic baseline (unless specified), were included as covariates following prior evidence [ 10 , 16 , 17 , 24 , 40 ]. Cancer characteristics included age at diagnosis, year of diagnosis, time between diagnosis and analytic baseline, stage, and tumor location.…”

Section: Methodsmentioning

confidence: 99%

“…Because individuals using antidepressants/anxiolytics may be more likely to report fewer anxiety- or depression-related symptoms, and common mental disorders are often measured using self-report symptoms, failure to account for use of psychotropics may lead to exposure misclassification. Additionally, because participants must have survived until the psychological assessment, analytic samples can include healthier individuals who may have better initial mental/physical states, resulting in potential selection bias [ 24 ].…”

Section: Introductionmentioning

confidence: 99%

Anxiety, Depression, and Colorectal Cancer Survival: Results from Two Prospective Cohorts

Trudel‐Fitzgerald

Tworoger

Zhang

et al. 2020

JCM

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Given the unalterable nature of most risk factors for colorectal cancer (CRC) survival (e.g., disease stage), identifying modifiable determinants is critical. We investigated whether anxiety and depression were related to CRC survival using data from the Nurses’ Health Study (NHS) and Health Professional Follow-up Study (HPFS). Participants who received a CRC diagnosis and provided information about anxiety (nNHS = 335; nHPFS = 232) and depression (nNHS = 893; nHPFS = 272) within 4 years of diagnosis were included. Cox regression models estimated hazard ratios (HR) and 95% confidence intervals (CI) of overall mortality, while controlling for covariates (sociodemographics, cancer characteristics, and lifestyle factors). Pooled risk estimates were derived from fixed effects meta-analyses of the cohorts. Among 1732 CRC patients, 814 deaths occurred during the 28-year follow-up. Each 1 standard deviation increase in anxiety or depression symptoms was associated with a similar 16% higher mortality risk (anxiety: 95% CI = 1.05–1.29; depression: 95% CI = 1.07–1.26). Comparable results were observed across all sensitivity analyses (introducing a 1-year lag, restricting to CRC-related mortality, considering potential behavioral pathways) and stratified models (cancer stage, sex). Our findings suggest greater anxiety and depression symptoms can not only impede adherence to healthy habits and reduce quality of life in cancer patients but could also be a marker for accelerated CRC progression.

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“…However, a limitation of extended longitudinal studies could be an increase in the number of dropouts (Gustavson et al, 2012). This is known as attrition concern can lead to the subsequent biases of auto-selection and experimental survival (Carmona-Bayonas et al, 2018). In other words, participants who reported all EMA assessments throughout a very long study could have different individual characteristics from those who not complete all the study.…”

Section: Profile Of the Populations Studied With Ema And Pamentioning

confidence: 99%

mHealth technology for ecological momentary assessment in physical activity research: a systematic review

Zapata-Lamana

Lalanza

Losilla

et al. 2020

PeerJ

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Objective To systematically review the publications on ecological momentary assessment (EMA) relating to physical activity (PA) behavior in order to classify the methodologies, and to identify the main mHealth technology-based tools and procedures that have been applied during the first 10 years since the emergence of smartphones. As a result of this review, we want to ask if there is enough evidence to propose the use of the term “mEMA” (mobile-based EMA). Design A systematic review according to PRISMA Statement (PROSPERO registration: CRD42018088136). Method Four databases (PsycINFO, CINALH, Medline and Web of Science Core Collection) were searched electronically from 2008 to February 2018. Results A total of 76 studies from 297 potential articles on the use of EMA and PA were included in this review. It was found that 71% of studies specifically used “EMA” for assessing PA behaviors but the rest used other terminology that also adjusted to the inclusion criteria. Just over half (51.3%) of studies (39) used mHealth technology, mainly smartphones, for collecting EMA data. The majority (79.5%) of these studies (31 out of 39) were published during the last 4 years. On the other hand, 58.8% of studies that only used paper-and-pencil were published during the first 3 years of the 10-year period analyzed. An accelerometer was the main built-in sensor used for collecting PA behavior by means of mHealth (69%). Most of the studies were carried out on young-adult samples, with only three studies in older adults. Women were included in 60% of studies, and healthy people in 82%. The studies lasted between 1 and 7 days in 57.9%, and between three and seven assessments per day were carried out in 37%. The most popular topics evaluated together with PA were psychological state and social and environmental context. Conclusions We have classified the EMA methodologies used for assessing PA behaviors. A total of 71% of studies used the term “EMA” and 51.3% used mHealth technology. Accelerometers have been the main built-in sensor used for collecting PA. The change of trend in the use of tools for EMA in PA coincides with the technological advances of the last decade due to the emergence of smartphones and mHealth technology. There is enough evidence to use the term mEMA when mHealth technology is being used for monitoring real-time lifestyle behaviors in natural situations. We define mEMA as the use of mobile computing and communication technologies for the EMA of health and lifestyle behaviors. It is clear that the use of mHealth is increasing, but there is still a lot to be gained from taking advantage of all the capabilities of this technology in order to apply EMA to PA behavior. Thus, mEMA methodology can help in the monitoring of healthy lifestyles under both subjective and objective perspectives. The tendency for future research should be the automatic recognition of the PA of the user without interrupting their behavior. The ecological information could be completed with voice messages, image captures or brief text selections on the touch screen made in real time, all managed through smartphone apps. This methodology could be extended when EMA combined with mHealth are used to evaluate other lifestyle behaviors.

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Top ten errors of statistical analysis in observational studies for cancer research

Cited by 21 publications

References 69 publications

DNA ploidy status, S-phase fraction, and p53 are not independent prognostic factors for survival in endometrioid endometrial carcinoma FIGO stage I–III

DNA ploidy status, S-phase fraction, and p53 are not independent prognostic factors for survival in endometrioid endometrial carcinoma FIGO stage I–III

Anxiety, Depression, and Colorectal Cancer Survival: Results from Two Prospective Cohorts

mHealth technology for ecological momentary assessment in physical activity research: a systematic review

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