Detecting Sentiment toward Emerging Infectious Diseases on Social Media: A Validity Evaluation of Dictionary-Based Sentiment Analysis.

Despite the popularity and efficiency of dictionary-based sentiment analysis (DSA) for public health research, limited empirical evidence has been produced about the validity of DSA and potential harms to the validity of DSA. A random sample of a second-hand Ebola tweet dataset was used to evaluate the validity of DSA compared to the manual coding approach and examine the influences of textual features on the validity of DSA. The results revealed substantial inconsistency between DSA and the manual coding approach. The presence of certain textual features such as negation can partially account for the inconsistency between DSA and manual coding. The findings imply that scholars should be careful and critical about findings in disease-related public health research that use DSA. Certain textual features should be more carefully addressed in DSA.

Social Enhancement and Compensation in Online Social Support among Cancer Patients: The Role of Social Network Properties.

Although several researchers have reported evidence that the benefits of Internet use depend on users' offline resources, the factors responsible for this phenomenon are not well understood. We examined a network-based explanation for social enhancement (i.e., rich get richer) and social compensation (i.e., poor get richer) in the context of received social support among adults coping with cancer. After first controlling for support received offline, we tested the role of two offline network properties in predicting support received online. The results were mostly consistent with social enhancement. Offline group affiliation was associated with greater levels of support received online. Additionally, significant indirect effects were observed from offline group affiliation to support received online through online group affiliation as well as from offline tie strength to support received online through online tie strength.

How Cancer Patients Benefit from Support Networks Offline and Online: Extending the Model of Structural-to-Functional Support.

Although social support is an indispensable resource for coping with illness, the connections among the structural properties of one's support network, received social support from offline and online network members, and well-being are not well understood. This study aims to extend the model of structural-to-functional support by distinguishing offline from online support networks and identifying different pathways through which these two networks contribute to patients' emotional well-being. Using data from 386 cancer patients, the results revealed that offline and online support networks were associated with patients' emotional well-being via different types of received support. Specifically, offline support network size was negatively associated with their emotional well-being via informational support received offline. Online support network size was positively associated with their emotional well-being via emotional support received online.

Multilayered social dynamics and depression among older adults: A 10-year cross-lagged analysis.

Depression in older adults is associated with decreased physical, cognitive, and social functioning, which in turn, are associated with increased mortality. Research has found that robust social networks can protect against depression, yet it is unclear whether the relationship between social ties and depression is reciprocal. Moreover, links between network connections at different social layers are not well understood. This study uses a representative sample with panel data collected between 2005 and 2016 to identify the influence of social network composition on subsequent depression and explore how various layers of human relationships (e.g., community vs. interpersonal level) influence one another. Results demonstrate multiple links between social connection and depression, and that the evolution of social networks in older adults is complex, with distinct mechanisms leading to positive and negative outcomes. Specifically, community involvement showed consistent benefits in reducing depression. In contrast, intimate partnerships appear to increase susceptibility to depression among older adults through exposure to the severe outcomes of partner loss. In addition, intimate partnerships reduce future interpersonal connections, whereas community involvement increases future interpersonal connections for older adults. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

A novel association test for rare variants based on algebraic statistics.

With the rapid growth of next-generation sequencing technology, more and more rare variants are available in the human genome. In recent years, the point of study has already changed direction to rare variants in genome-wide association studies (GWAS). Although a variety of approaches have been proposed to test associations between rare variants and phenotypes of interest, it is far from the end of this problem, and it is worth exploring new statistical methods based on special features of rare variants. As we all know, the most direct way is to evaluate the association in a two-way contingency table if the phenotype is a discrete variable. The numbers of observations are very close or equal to 0s for most of cells in the contingency table due to the extremely low mutation rates of rare variants. In this paper, we propose a novel association test for rare variants based on a generalization of Fisher's exact test, and the p-value of this exact test can be computed under the multivariate hypergeometric distribution in the framework of algebraic statistics. Simulation results show that our proposed method outperforms the existing methods, despite there is heterogeneity among causal variants. We also successfully apply our method into the genetic association study of coronary artery disease and hypertension from the Wellcome Trust Case Control Consortium.

Confidant Network and Interpersonal Communication Associations with Depression in Older Adulthood.

Social networks contribute to the well-being and longevity of older adults, yet very little research to date has attempted to identify communicative mechanisms that explain the link between social networks and health. This study identified and tested two communicative mechanisms, openness and criticism, as mediators between confidant network size, confidant network density, and depression in a sample of 2,249 Americans over the age of 60. The data suggest that openness with friends and family mediate the relationship between network factors (size and density) and depression, while criticism from friends and family also mediate the relationship between network properties (size and density) and depression but less consistently (e.g., friend criticism only mediated the relationship with density). In general, network size appears to increase exposure to the positive outcomes of openness but also increase the negative outcomes of criticism; the role of network density is more complicated. The varied direction of the mediation associations are discussed along with implications for network and communication theorists and those who work with older adults.

A permutation method for detecting trend correlations in rare variant association studies.

In recent years, there has been an increasing interest in detecting disease-related rare variants in sequencing studies. Numerous studies have shown that common variants can only explain a small proportion of the phenotypic variance for complex diseases. More and more evidence suggests that some of this missing heritability can be explained by rare variants. Considering the importance of rare variants, researchers have proposed a considerable number of methods for identifying the rare variants associated with complex diseases. Extensive research has been carried out on testing the association between rare variants and dichotomous, continuous or ordinal traits. So far, however, there has been little discussion about the case in which both genotypes and phenotypes are ordinal variables. This paper introduces a method based on the γ-statistic, called OV-RV, for examining disease-related rare variants when both genotypes and phenotypes are ordinal. At present, little is known about the asymptotic distribution of the γ-statistic when conducting association analyses for rare variants. One advantage of OV-RV is that it provides a robust estimation of the distribution of the γ-statistic by employing the permutation approach proposed by Fisher. We also perform extensive simulations to investigate the numerical performance of OV-RV under various model settings. The simulation results reveal that OV-RV is valid and efficient; namely, it controls the type I error approximately at the pre-specified significance level and achieves greater power at the same significance level. We also apply OV-RV for rare variant association studies of diastolic blood pressure.

Exploring User Needs for a Mobile Behavioral-Sensing Technology for Depression Management: Qualitative Study.

BACKGROUND: Today, college students are dealing with depression at some of the highest rates in decades. As the primary mental health service provider, university counseling centers are limited in their capacity and efficiency to provide mental health care due to time constraints and reliance on students' self-reports. A mobile behavioral-sensing platform may serve as a solution to enhance the efficiency and accessibility of university counseling services. OBJECTIVE: The main objectives of this study are to (1) understand the usefulness of a mobile sensing platform (ie, iSee) in improving counseling services and assisting students' self-management of their depression conditions, and (2) explore what types of behavioral targets (ie, meaningful information extracted from raw sensor data) and feedback to deliver from both clinician and students' perspectives. METHODS: We conducted semistructured interviews with 9 clinicians and 12 students with depression recruited from a counseling center at a large Midwestern university. The interviews were 40-50 minutes long and were audio recorded and transcribed. The interview data were analyzed using thematic analysis with an inductive approach. Clinician and student interviews were analyzed separately for comparison. The process of extracting themes involved iterative coding, memo writing, theme revisits, and refinement. RESULTS: From the clinician perspective, the mobile sensing platform helps to improve counseling service by providing objective evidence for clinicians and filling gaps in clinician-patient communication. Clinicians suggested providing students with their sensed behavioral targets organized around personalized goals. Clinicians also recommended delivering therapeutic feedback to students based on their sensed behavioral targets, including positive reinforcement, reflection reminders, and challenging negative thoughts. From the student perspective, the mobile sensing platform helps to ease continued self-tracking practices. Students expressed their need for integrated behavioral targets to understand correlations between behaviors and depression. They also pointed out that they would prefer to avoid seeing negative feedback. CONCLUSIONS: Although clinician and student participants shared views on the advantages of iSee in supporting university counseling, they had divergent opinions on the types of behavioral targets and feedback to be provided via iSee. This exploratory work gained initial insights into the design of a mobile sensing platform for depression management and informed a more conclusive research project for the future.

Diffusion size and structural virality: The effects of message and network features on spreading health information on twitter.

Relying on diffusion of innovation theory, this study examines the impacts of perceived message features and network characteristics on size (i.e., the number of retweets a message receives) and structural virality (i.e., quantified distinction between broadcast and viral diffusion) of information diffusion on Twitter. The study collected 425 unique tweets posted by CDC during a 17-week period and constructed a diffusion tree for each unique tweet. Findings indicated that, with respect to message features, perceived efficacy after reading a tweet positively predicted diffusion size of the tweet, whereas perceived susceptibility to a health condition after reading a tweet positively predicted structural virality of the tweet. Perceived negative emotion positively predicted both size and structural virality. With respect to network features, the level of involvement of brokers in diffusing a tweet increased the tweet's structural virality. Theoretical and practical implications were discussed on disseminating health information via broadcasting and viral diffusion on social media.

Online Self-Tracking Groups to Increase Fruit and Vegetable Intake: A Small-Scale Study on Mechanisms of Group Effect on Behavior Change.

BACKGROUND: Web-based interventions with a self-tracking component have been found to be effective in promoting adults' fruit and vegetable consumption. However, these interventions primarily focus on individual- rather than group-based self-tracking. The rise of social media technologies enables sharing and comparing self-tracking records in a group context. Therefore, we developed an online group-based self-tracking program to promote fruit and vegetable consumption. OBJECTIVE: This study aims to examine (1) the effectiveness of online group-based self-tracking on fruit and vegetable consumption and (2) characteristics of online self-tracking groups that make the group more effective in promoting fruit and vegetable consumption in early young adults. METHODS: During a 4-week Web-based experiment, 111 college students self-tracked their fruit and vegetable consumption either individually (ie, the control group) or in an online group characterized by a 2 (demographic similarity: demographically similar vs demographically diverse) × 2 (social modeling: incremental change vs ideal change) experimental design. Each online group consisted of one focal participant and three confederates as group members or peers, who had their demographics and fruit and vegetable consumption manipulated to create the four intervention groups. Self-reported fruit and vegetable consumption were assessed using the Food Frequency Questionnaire at baseline and after the 4-week experiment. RESULTS: Participants who self-tracked their fruit and vegetable consumption collectively with other group members consumed more fruits and vegetables than participants who self-tracked individually (P=.01). The results did not show significant main effects of demographic similarity (P=.32) or types of social modeling (P=.48) in making self-tracking groups more effective in promoting fruit and vegetable consumption. However, additional analyses revealed the main effect of performance discrepancy (ie, difference in fruit and vegetable consumption between a focal participant and his/her group members during the experiment), such that participants who had a low performance discrepancy from other group members had greater fruit and vegetable consumption than participants who had a high performance discrepancy from other group members (P=.002). A mediation test showed that low performance discrepancy led to greater downward contrast (b=-0.78, 95% CI -2.44 to -0.15), which in turn led to greater fruit and vegetable consumption. CONCLUSIONS: Online self-tracking groups were more effective than self-tracking alone in promoting fruit and vegetable consumption for early young adults. Low performance discrepancy from other group members lead to downward contrast, which in turn increased participants' fruit and vegetable consumption over time. The study highlighted social comparison processes in online groups that allow for sharing personal health information. Lastly, given the small scale of this study, nonsignificant results with small effect sizes might be subject to bias.

Pathways for best practice diffusion: the structure of informal relationships in Canada's long-term care sector.

BACKGROUND: Initiatives to accelerate the adoption and implementation of evidence-based practices benefit from an association with influential individuals and organizations. When opinion leaders advocate or adopt a best practice, others adopt too, resulting in diffusion. We sought to identify existing influence throughout Canada's long-term care sector and the extent to which informal advice-seeking relationships tie the sector together as a network. METHODS: We conducted a sociometric survey of senior leaders in 958 long-term care facilities operating in 11 of Canada's 13 provinces and territories. We used an integrated knowledge translation approach to involve knowledge users in planning and administering the survey and in analyzing and interpreting the results. Responses from 482 senior leaders generated the names of 794 individuals and 587 organizations as sources of advice for improving resident care in long-term care facilities. RESULTS: A single advice-seeking network appears to span the nation. Proximity exhibits a strong effect on network structure, with provincial inter-organizational networks having more connections and thus a denser structure than interpersonal networks. We found credible individuals and organizations within groups (opinion leaders and opinion-leading organizations) and individuals and organizations that function as weak ties across groups (boundary spanners and bridges) for all studied provinces and territories. A good deal of influence in the Canadian long-term care sector rests with professionals such as provincial health administrators not employed in long-term care facilities. CONCLUSIONS: The Canadian long-term care sector is tied together through informal advice-seeking relationships that have given rise to an emergent network structure. Knowledge of this structure and engagement with its opinion leaders and boundary spanners may provide a route for stimulating the adoption and effective implementation of best practices, improving resident care and strengthening the long-term care advice network. We conclude that informal relational pathways hold promise for helping to transform the Canadian long-term care sector.

Exploring Willingness to Participate in Clinical Trials by Ethnicity.

African-Americans and Hispanic-Americans are disproportionately affected by cancer, yet underrepresented in cancer clinical trials. Because of this, it is important to understand how attitudes and beliefs about clinical trials vary by ethnicity. A national, random sample of 860 adults was given an online survey about attitudes toward clinical trials. We examined willingness to participate in clinical trials, attitudes toward clinical trials, trust in doctors, attitudes toward alternative and complementary medicine, and preferred information channels. Results indicate that African-American and Hispanic-American participants have more negative attitudes about clinical trials, more distrust toward doctors, more interest in complementary and alternative medicine, and less willingness to participate in clinical trials than white/non-Hispanics, although specific factors affecting willingness to participate vary. The channels people turn to for information on clinical trials also varied by ethnicity. These results help explain the ethnic disparities in cancer clinical trial enrollment by highlighting some potential underlying causes and drawing attention to areas of importance to these groups.

Research on Social Networking Sites and Social Support from 2004 to 2015: A Narrative Review and Directions for Future Research.

The article presents a narrative review of scholarship on social support through social networking sites (SNSs) published from 2004 to 2015. By searching keywords related to social support and SNSs in major databases for social sciences, we identified and content analyzed directly relevant articles (N = 88). The article summarizes the prevalence of theory usage; the function of theory usage (e.g., testing a theory, developing a theory); major theories referenced; and methodologies, including research designs, measurement, and the roles of social support and SNS examined in this literature. It also reports four themes identified across the studies, indicating the trends in the current research. Based on the review, the article presents a discussion about study sites, conceptualization of social support, theoretical coherence, the role of social networks, and the dynamic relationships between SNS use and social support, which points out potential avenues for shaping a future research agenda.

A Comparison Between Caucasians and African Americans in Willingness to Participate in Cancer Clinical Trials: The Roles of Knowledge, Distrust, Information Sources, and Religiosity.

This study aims to (a) examine the roles of knowledge, distrust in medical professionals, information sources, and 2 dimensions of religiosity (i.e., religious activity and religious belief) in influencing willingness to participate (WTP) in cancer clinical trials and to (b) compare the results for Caucasians and African Americans in order to inform future recruitment. An online survey was fielded via a Knowledge Networks panel with a nationally representative sample including 478 Caucasians and 173 African Americans. The results showed that distrust in medical professionals was a strong barrier to WTP for both ethnic groups, whereas factual knowledge about trial procedures was not associated with WTP for either ethnic group. Seeking trial information from doctors was positively associated with WTP for Caucasians; seeking trial information from hospitals was positively associated with WTP for African Americans. More interestingly, levels of religious activity negatively predicted WTP for Caucasians but positively predicted WTP for African Americans. Self-reported religious belief was not associated with WTP for either ethnic group. In sum, although distrust is a common barrier to WTP, the influence of preferred information sources and religious activity on WTP varies as a function of ethnicity.

Your Health Buddies Matter: Preferential Selection and Social Influence on Weight Management in an Online Health Social Network.

A growing number of online social networks are designed with the intention to promote health by providing virtual space wherein individuals can seek and share information and support with similar others. Research has shown that real-world social networks have a significant influence on one's health behavior and outcomes. However, there is a dearth of studies on how individuals form social networks in virtual space and whether such online social networks exert any impact on individuals' health outcomes. Built on the Multi-Theoretical Multilevel (MTML) framework and drawing from literature on social influence, this study examined the mechanisms underlying the formation of an online health social network and empirically tested social influence on individual health outcomes through the network. Situated in a weight management social networking site, the study tracked a health buddy network of 709 users and their weight management activities and outcomes for 4 months. Actor-based modeling was used to test the joint dynamics of preferential selection and social influence among health buddies. The results showed that baseline, inbreeding, and health status homophily significantly predicted preferential selection of health buddies in the weight management social networking site, whereas self-interest in seeking experiential health information did not. The study also found peer influence of online health buddy networks on individual weight outcomes, such that an individual's odds of losing weight increased if, on average, the individual's health buddies were losing weight.

Propagation of Information About Preexposure Prophylaxis (PrEP) for HIV Prevention Through Twitter.

Previous literature has suggested that examining Twitter messages can be productive for studying how the public shares and spreads health information on social media. Preexposure prophylaxis (PrEP) is a promising approach to HIV prevention, yet there are many issues that may influence its effective implementation. This study examined social representations of PrEP on Twitter. One thousand four hundred and thirty-five Tweets were collected and 774 English Tweets were content-analyzed to explore propagation of various issues around daily oral PrEP, as well as characteristics of the sources of those Tweets. We also examined how Twitter message content influenced information propagation. Our findings revealed that PrEP-related information on Twitter covered a wide range of issues, and individual users constituted the majority of the Tweet creators among all the sources, including news media, nonprofit and academic groups, and commercial entities. Using Poisson regression, we also found that a Tweet's affective tone was a significant predictor of message propagation frequency. Implications for health practitioners are discussed.