Survey Non-Response in COVID-19 Times: The Case of the Labour Force Survey.

During the COVID-19 pandemic, labour-force survey non-response rates have surged in many countries. We show that in the case of the Canadian Labour Force Survey (LFS), the bulk of this increase is due to the suspension of in-person interviews following the adoption of telework within Federal agencies, including Statistics Canada. Individuals with vulnerabilities to the COVID-19 economic shock have been harder to reach and have been gradually less and less represented in the LFS during the pandemic. We present evidence suggesting that the decline in employment and labour-force participation have been underestimated over the March-July 2020 period. We argue that these non-response issues are moderate when analyzing aggregate outcomes, but that researchers should exert caution when gauging the robustness of estimates for subgroups. We discuss practical implications for research based on the LFS, such as the consequences for panels and the choice of public-use versus master files of the LFS.

Pendant la pandémie de COVID-19, le taux de non-réponse aux enquêtes auprès de la population active a explosé dans beaucoup de pays. Nous montrons que dans le cas de l'Enquête canadienne sur la population active (EPA), le gros de cette hausse s'explique par la suspension des entrevues en personne qui a suivi l'adoption du télétravail dans les agences fédérales, y compris à Statistique Canada. Les personnes vulnérables au choc économique de la COVID-19 ont été plus difficiles à joindre et ont été de moins en moins représentées dans l'EPA au cours de la pandémie. Nous montrons, preuves à l'appui, que la diminution de l'emploi et de la participation à la main-d'œuvre est sous-estimée pour la période de mars à juillet 2020. Nous soutenons que la gravité de ces problèmes de non-réponses est modérée quand il s'agit d'analyser des résultats agrégés mais que la prudence s'impose dans l'évaluation de la robustesse des estimations pour les sous-groupes. Nous présentons les conséquences pratiques de cette situation pour les travaux qui reposent sur l'EPA, telles que les effets sur les panels et le choix entre données à grande diffusion et fichiers principaux de l'EPA.

Determinants of participation in a longitudinal survey during the COVID-19 pandemic: the case of a low-infection country.

A large-scale crisis, such as the COVID-19 pandemic, has the potential to affect non-response in cross-sectional and longitudinal surveys. This study utilises a longitudinal survey, conducted prior to and during the COVID-19 pandemic, to examine the factors associated with participation in longitudinal surveys during the COVID-19 period, and how this has changed from prior to the pandemic. We find that a number of demographic groups are more likely to be non-responders to COVID-19 surveys, despite having completed pre-COVID surveys, as well as a number of other economic and personality factors. Reassuringly though, there were many more factors that did not have an association. The findings also highlight that two simple questions (with a low time cost) on subjective survey experience early in the pandemic were highly useful in predicting future survey participation. These findings can help to support survey practitioners and data collection companies to develop more robust response improvement strategies during the COVID-19 period.

Later one knows better: the over-reporting of short-time work in firm surveys.

Short-time work (STW) in Germany allows for a lot of flexibility in actual usage. Ex ante, firms notify the Employment Agency about the total number of employees eligible, and, up to the total granted, firms can flexibly choose how many employees actually use STW. In firm-level surveys, which provide timely information on STW in Germany, over-reporting of the number of employees on STW is prevalent. This study explores reasons for STW over-reporting based on a high-frequency and low-cost survey initiated during the Covid-19-pandemic (BeCovid) and a low-frequency and high-cost long-running survey (BP). Merging administrative records on actual use of STW, firms that use STW prove more likely to participate in the BeCovid survey. Multi-establishment firms over-report STW because they tend to report STW for all subfirms. The BP uses more interview time and confirms the over-reporting of STW use in the survey month, while-crucially-the over-reporting drops sharply with a few months of retrospection.

Insulin Pump Treatment in Adults with Type 1 Diabetes in the Capital Region of Denmark: Design and Cohort Characteristics of the Steno Tech Survey.

INTRODUCTION: Insulin pump therapy can improve quality of life and glycaemic outcomes for many people with type 1 diabetes (T1D). The multidimensional Steno Tech Survey study aims to investigate why some insulin pump users do not achieve treatment goals. In this article, we present the study design and analyse differences in population characteristics between responders and non-responders. METHODS: In June 2020, all 1591 insulin pump users (≥ 18 years) in the Capital Region of Denmark were invited to participate in an online questionnaire that evaluated several dimensions of insulin pump self-management and psychosocial health. Demographic, socioeconomic and clinical characteristics, including age, sex and HbA1c, of the cohort were identified via national registries. Predictors of questionnaire response/non-response were explored with logistic regression analysis. RESULTS: In the full study population, 58% were female, median age was 42 years and median HbA1c was 58 mmol/mol (7.5%); 30% had HbA1c < 53 mmol/mol (7.0%). In total, 770 individuals (48%) responded to the questionnaire. Logistic regression analysis showed that 50+ years of age (odds ratio [OR] = 2.3, 95% confidence interval [CI]: 1.4-3.8), female sex (OR = 1.3, CI: 1.02-1.6), being married (OR = 1.8, CI: 1.3-2.4) and having long higher education (OR = 1.6, CI: 1.004-2.5) were significantly associated with a higher likelihood of responding to the survey; the opposite was found for HbA1c from 64 to < 75 mmol (8.0-9.0%) (OR = 0.6, CI: 0.4-0.8) and HbA1c ≥ 75 mmol/mol (≥ 9.0%) (OR = 0.2, CI: 0.1-0.3). CONCLUSIONS: The established Steno Tech cohort enables future analysis of a range of psychosocial and behavioural aspects of insulin pump self-management. Interpretation and generalization of findings should consider observed differences between responders and non-responders.

Evolution of SARS-CoV-2-Neutralizing Antibodies after Two Standard Dose Vaccinations, Risk Factors for Non-Response and Effect of a Third Dose Booster Vaccination in Non-Responders on Hemodialysis: A Prospective Multi-Centre Cohort Study.

The aim of this investigation was to determine the effect of SARS-Cov-2 vaccination in hemodialysis patients, search for risk factors for non- or low-response, and to measure the effect of a third booster vaccination in non- or low-responders. Methods SARS-CoV-2 IgG antibodies and the virus-neutralizing capacity were measured 4-5 weeks after a full standard vaccination in 95 chronic hemodialysis patients and 60 controls. IgG titers > 30 AU/mL served to classify participants as responders. Multivariable binary logistic regression analysis was used to search for risk factors of reduced vaccination success. Patients with vaccination failure were offered a third booster dosage. Results 82.1% of the patient cohort as compared to 98.3% of the healthy control group were able to mount SARS-CoV-2 titers above 30 AU/mL after two standard vaccine doses. Mean IgG antibody titers were lower in hemodialysis patients than controls (78 ± 35 vs. 90 ± 20 AU/mL, p = 0.002). Multivariable binary logistic regression analysis showed age and immunosuppressive medication as major risk factors for vaccination failure with a decreased probability of successful vaccination of -6.1% (95% CI -1.2 to -10.9) per increase in age of one year and -87.4% (95% CI -98.0 to -21.5) in patients on immunosuppressive therapy (crude odds ratio for vaccination failure for immunosuppressive therapy 6.4). Ten out of 17 patients with non-response to vaccination were offered a third dose. Booster vaccination after the second dose induced an increase in effective antibody titers of >30 AU/mL in seven out of ten patients 4-5 weeks later (70%). Conclusion Standard SARS-CoV-2 vaccination schemes are highly effective in mounting protective neutralizing IgG antibodies in chronic hemodialysis patients. Nevertheless, response to vaccination is diminished as compared to a healthy control group. Major risk factors for vaccination failure are older age and immunosuppressive therapy. In non- or low-responders to standard vaccination a third booster vaccination was able to induce effective antibody titers in about 70% of patients, indicating that a third booster vaccination might be preferable to decreasing immunosuppressive therapy.

Analytical methods used in estimating the prevalence of HIV/AIDS from demographic and cross-sectional surveys with missing data: a systematic review.

BACKGROUND: Sero- prevalence studies often have a problem of missing data. Few studies report the proportion of missing data and even fewer describe the methods used to adjust the results for missing data. The objective of this review was to determine the analytical methods used for analysis in HIV surveys with missing data. METHODS: We searched for population, demographic and cross-sectional surveys of HIV published from January 2000 to April 2018 in Pub Med/Medline, Web of Science core collection, Latin American and Caribbean Sciences Literature, Africa-Wide Information and Scopus, and by reviewing references of included articles. All potential abstracts were imported into Covidence and abstracts screened by two independent reviewers using pre-specified criteria. Disagreements were resolved through discussion. A piloted data extraction tool was used to extract data and assess the risk of bias of the eligible studies. Data were analysed through a quantitative approach; variables were presented and summarised using figures and tables. RESULTS: A total of 3426 citations where identified, 194 duplicates removed, 3232 screened and 69 full articles were obtained. Twenty-four studies were included. The response rate for an HIV test of the included studies ranged from 32 to 96% with the major reason for the missing data being refusal to consent for an HIV test. Complete case analysis was the primary method of analysis used, multiple imputations 11(46%) was the most advanced method used, followed by the Heckman's selection model 9(38%). Single Imputation and Instrumental variables method were used in only two studies each, with 13(54%) other different methods used in several studies. Forty-two percent of the studies applied more than two methods in the analysis, with a maximum of 4 methods per study. Only 6(25%) studies conducted a sensitivity analysis, while 11(46%) studies had a significant change of estimates after adjusting for missing data. CONCLUSION: Missing data in survey studies is still a problem in disease estimation. Our review outlined a number of methods that can be used to adjust for missing data on HIV studies; however, more information and awareness are needed to allow informed choices on which method to be applied for the estimates to be more reliable and representative.

Uncovering survivorship bias in longitudinal mental health surveys during the COVID-19 pandemic.

AIMS: Markedly elevated adverse mental health symptoms were widely observed early in the coronavirus disease-2019 (COVID-19) pandemic. Unlike the U.S., where cross-sectional data indicate anxiety and depression symptoms have remained elevated, such symptoms reportedly declined in the U.K., according to analysis of repeated measures from a large-scale longitudinal study. However, nearly 40% of U.K. respondents (those who did not complete multiple follow-up surveys) were excluded from analysis, suggesting that survivorship bias might partially explain this discrepancy. We therefore sought to assess survivorship bias among participants in our longitudinal survey study as part of The COVID-19 Outbreak Public Evaluation (COPE) Initiative. METHODS: Survivorship bias was assessed in 4039 U.S. respondents who completed surveys including the assessment of mental health as part of The COPE Initiative in April 2020 and were invited to complete follow-up surveys. Participants completed validated screening instruments for symptoms of anxiety, depression and insomnia. Survivorship bias was assessed for (1) demographic differences in follow-up survey participation, (2) differences in initial adverse mental health symptom prevalence adjusted for demographic factors and (3) differences in follow-up survey participation based on mental health experiences adjusted for demographic factors. RESULTS: Adjusting for demographics, individuals who completed only one or two out of four surveys had significantly higher prevalence of anxiety and depression symptoms in April 2020 (e.g. one-survey v. four-survey, anxiety symptoms, adjusted prevalence ratio [aPR]: 1.30, 95% confidence interval [CI]: 1.08-1.55, p = 0.0045; depression symptoms, aPR: 1.43, 95% CI: 1.17-1.75, p = 0.00052). Moreover, individuals who experienced incident anxiety or depression symptoms had significantly higher adjusted odds of not completing follow-up surveys (adjusted odds ratio [aOR]: 1.68, 95% CI: 1.22-2.31, p = 0.0015, aOR: 1.56, 95% CI: 1.15-2.12, p = 0.0046, respectively). CONCLUSIONS: Our findings reveal significant survivorship bias among longitudinal survey respondents, indicating that restricting analytic samples to only respondents who provide repeated assessments in longitudinal survey studies could lead to overly optimistic interpretations of mental health trends over time. Cross-sectional or planned missing data designs may provide more accurate estimates of population-level adverse mental health symptom prevalence than longitudinal surveys.

Survey Fatigue During the COVID-19 Pandemic: An Analysis of Neurosurgery Survey Response Rates.

Background: The COVID-19 pandemic has caused a surge in research activity while restricting data collection methods, leading to a rise in survey-based studies. Anecdotal evidence suggests this increase in neurosurgical survey dissemination has led to a phenomenon of survey fatigue, characterized by decreased response rates and reducing the quality of data. This paper aims to analyze the effect of COVID-19 on neurosurgery surveys and their response rates, and suggest strategies for improving survey data collection. Methods: A search was conducted on March 20, 2021, on Medline and EMBASE. This included the terms "neurosurgery," "cranial surgery," "spine surgery," and "survey" and identified surveys written in English, on a neurosurgical topic, distributed to neurosurgeons, trainees, and medical students. Results were screened by two authors according to these inclusion criteria, and included articles were used for data extraction, univariable, and bivariable analysis with Fisher's exact-test, Wilcoxon rank-sum test, and Spearman's correlation. Results: We included 255 articles in our analysis, 32.3% of which were published during the COVID-19 pandemic. Surveys had an average of 25.6 (95% CI = 22.5-28.8) questions and were mostly multiple choice (78.8%). They were disseminated primarily by email (75.3%, 95% CI = 70.0-80.6%) and there was a significant increase in dissemination via social media during the pandemic (OR = 3.50, 95% CI = 1.30-12.0). COVID-19 surveys were distributed to more geographical regions than pre-pandemic surveys (2.1 vs. 1.5, P = 0.01) and had higher total responses (247.0 vs. 206.4, P = 0.01), but lower response rates (34.5 vs. 51.0%, P < 0.001) than pre-COVID-19 surveys. Conclusion: The rise in neurosurgical survey distribution during the COVID-19 pandemic has led to survey fatigue, reduced response rates, and data collection quality. We advocate for population targeting to avoid over-researching, collaboration between research teams to minimize duplicate surveys, and communication with respondents to convey study importance, and we suggest further strategies to improve response rates in neurosurgery survey data collection.