Identifying the Most Effective Recruitment Strategy Using Financial Reimbursements for a Web-Based Peer Network Study With Young People Aged 16-18 Years: Protocol for a Randomized Controlled Trial

BACKGROUND

Peers are an important determinant of health and well-being during late adolescence; however, there is limited quantitative research examining peer influence. Previous peer network research with adolescents faced methodological limitations and difficulties recruiting young people.

OBJECTIVE

This study aims to determine whether a web-based peer network survey is effective at recruiting adolescent peer networks by comparing 2 strategies for reimbursement.

METHODS

This study will use a 2-group randomized trial design to test the effectiveness of reimbursements for peer referral in a web-based cross-sectional peer network survey. Young people aged 16-18 years recruited through Instagram, Snapchat, and a survey panel will be randomized to receive either scaled group reimbursement (the experimental group) or fixed individual reimbursement (the control group). All participants will receive a reimbursement of Aus $5 (US $3.70) for their own survey completion. In the experimental group (scaled group reimbursement), all participants within a peer network will receive an additional Aus $5 (US $3.70) voucher for each referred participant who completes the study, up to a maximum total value of Aus $30 (US $22.20) per participant. In the control group (fixed individual reimbursement), participants will only be reimbursed for their own survey completion. Participants' peer networks are assessed during the survey by asking about their close friends. A unique survey link will be generated to share with the participant's nominated friends for the recruitment of secondary participants. Outcomes are the proportion of a participant's peer network and the number of referred peers who complete the survey. The required sample size is 306 primary participants. Using a multilevel logistic regression model, we will assess the effect of the reimbursement intervention on the proportion of primary participants' close friends who complete the survey. The secondary aim is to determine participant characteristics that are associated with successfully recruiting close friends. Young people aged 16-18 years were involved in the development of the study design through focus groups and interviews (n=26).

RESULTS

Participant recruitment commenced in 2022.

CONCLUSIONS

A longitudinal web-based social network study could provide important data on how social networks and their influence change over time. This trial aims to determine whether scaled group reimbursement can increase the number of peers referred. The outcomes of this trial will improve the recruitment of young people to web-based network studies of sensitive health issues.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/44813.

Pragmatics aid referent disambiguation and word learning in young children and adults

How do children succeed in learning a word? Research has shown robustly that, in ambiguous labeling situations, young children assume novel labels to refer to unfamiliar rather than familiar objects. However, ongoing debates center on the underlying mechanism: Is this behavior based on lexical constraints, guided by pragmatic reasoning, or simply driven by children's attraction to novelty? Additionally, recent research has questioned whether children's disambiguation leads to long-term learning or rather indicates an attentional shift in the moment of the conversation. Thus, we conducted a pre-registered online study with 2- and 3-year-olds and adults. Participants were presented with unknown objects as potential referents for a novel word. Across conditions, we manipulated whether the only difference between both objects was their relative novelty to the participant or whether, in addition, participants were provided with pragmatic information that indicated which object the speaker referred to. We tested participants' immediate referent selection and their retention after 5 min. Results revealed that when given common ground information both age groups inferred the correct referent with high success and enhanced behavioral certainty. Without this information, object novelty alone did not guide their selection. After 5 min, adults remembered their previous selections above chance in both conditions, while children only showed reliable learning in the pragmatic condition. The pattern of results indicates how pragmatics may aid referent disambiguation and learning in both adults and young children. From early ontogeny on, children's social-cognitive understanding may guide their communicative interactions and support their language acquisition. RESEARCH HIGHLIGHTS: We tested how 2-3-year-olds and adults resolve referential ambiguity without any lexical cues. In the pragmatic context both age groups disambiguated novel word-object-mappings, while object novelty alone did not guide their referent selection. In the pragmatic context, children also showed increased certainty in disambiguation and retained new word-object-mappings over time. These findings contribute to the ongoing debate on whether children learn words on the basis of domain-specific constraints, lower-level associative mechanisms, or pragmatic inferences.

Understanding preschoolers' word learning success in different scenarios: disambiguation meets statistical learning and eBook reading

Children's ability to learn new words during their preschool years is crucial for further academic success. Previous research suggests that children rely on different learning mechanisms to acquire new words depending on the available context and linguistic information. To date, there is limited research integrating different paradigms to provide a cohesive view of the mechanisms and processes involved in preschool children's word learning. We presented 4 year-old children (n = 47) with one of three different novel word-learning scenarios to test their ability to connect novel words to their correspondent referents without explicit instruction to do so. The scenarios were tested with three exposure conditions of different nature: (i) mutual exclusivity-target novel word-referent pair presented with a familiar referent, prompting fast-mapping via disambiguation, (ii) cross-situational-target novel word-referent pair presented next to an unfamiliar referent prompting statistically tracking the target pairs across trials, and (iii) eBook - target word-referent pairs presented within an audio-visual electronic storybook (eBook), prompting inferring meaning incidentally. Results show children succeed at learning the new words above chance in all three scenarios, with higher performance in eBook and mutual exclusivity than in cross-situational word learning. This illustrates children's astounding ability to learn while coping with uncertainty and varying degrees of ambiguity, which are common in real-world situations. Findings extend our understanding of how preschoolers learn new words more or less successfully depending on specific word learning scenarios, which should be taken into account when working on vocabulary development for school readiness in the preschool years.

Children's disambiguation of novel words varies by the number and position of phonological contrasts

Young children often make pragmatic assumptions when learning new words. For example, they assume that a speaker who uses different words intends to refer to different things - the so-called principle of contrast. We used a standard disambiguation task to explore whether children's assumptions about contrast depend on how much words differ. Three- to 6-year-olds heard pairs of words that differed in terms of the number, position, and types of phonological contrasts. Results indicate that children were less likely to disambiguate words differing by one phoneme than words differing by two or more phonemes, particularly when those one-phoneme differences were located at the beginning or end of the words (as in fim/vim). Overall, the findings suggest that children's pragmatic assumptions about two contrasting words depend not only on if words differ, but also on how they differ.

The role of prosodic and visual information in disambiguating wh-indeterminates: The case of Korean three-year-olds

In Korean language, questions containing ambiguous wh-words may be interpreted as either wh-questions or yes-no questions. This study investigated 43 Korean three-year-olds' ability to disambiguate eight indeterminate questions using prosodic and visual cues. The intonation of each question provided a cue as to whether it should be interpreted as a wh-question or a yes-no question. The questions were presented alongside picture stimuli, which acted as either a matched (presentation of corresponding auditory-visual stimuli) or a mismatched contextual cue (presentation conflicting auditory-visual stimuli). Like adults, the children preferred to comprehend questions involving ambiguous wh-words as wh-questions, rather than yes-no questions. In addition, children were as effective as adults in disambiguating indeterminate questions using prosodic cues regardless of the visual cue. However, when confronted with conflicting auditory-visual stimuli (mismatched), the quality of children's responses was less accurate than adults' responses.

Disambiguation of psychotherapy: a search for meaning

This analysis identifies the significant problem of ambiguity, variation and vagueness in relation to the intervention described as 'psychotherapy'. Its purpose is to raise international awareness of this problem and alternative solutions.

Maternal transmission of SARS-COV-2 to the neonate, and possible routes for such transmission: a systematic review and critical analysis

Background

Early reports of COVID‐19 in pregnancy described management by caesarean, strict isolation of the neonate and formula feeding. Is this practice justified?

Objective

To estimate the risk of the neonate becoming infected with SARS‐CoV‐2 by mode of delivery, type of infant feeding and mother‐infant interaction.

Search strategy

Two biomedical databases were searched between September 2019 and June 2020.

Selection criteria

Case reports or case series of pregnant women with confirmed COVID‐19, where neonatal outcomes were reported.

Data collection and analysis

Data were extracted on mode of delivery, infant infection status, infant feeding and mother–infant interaction. For reported infant infection, a critical analysis was performed to evaluate the likelihood of vertical transmission.

Main results

Forty nine studies included information on mode of delivery and infant infection status for 655 women and 666 neonates. In all, 28/666 (4%) tested positive postnatally. Of babies born vaginally, 8/292 (2.7%) tested positivecompared with 20/374 (5.3%) born by Caesarean. Information on feeding and baby separation were often missing, but of reported breastfed babies 7/148 (4.7%) tested positive compared with 3/56 (5.3%) for reported formula fed ones. Of babies reported as nursed with their mother 4/107 (3.7%) tested positive, compared with 6/46 (13%) for those who were reported as isolated.

Conclusions

Neonatal COVID‐19 infection is uncommon, rarely symptomatic, and the rate of infection is no greater when the baby is born vaginally, breastfed or remains with the mother.

Tweetable abstract

Risk of neonatal infection with COVID‐19 by delivery route, infant feeding and mother‐baby interaction.

Risk of neonatal infection with COVID‐19 by delivery route, infant feeding and mother‐baby interaction.

This article includes Author Insights, a video abstract available at https://vimeo.com/rcog/authorinsights16362

When slowing down processing helps learning: Lexico-semantic structure supports retention, but interferes with disambiguation of novel object-label mappings

This project explores how children disambiguate and retain novel object-label mappings in the face of semantic similarity. Burgeoning evidence suggests that semantic structure in the developing lexicon promotes word learning in ostensive contexts, whereas other findings indicate that semantic similarity interferes with and temporarily slows familiar word recognition. This project explores how these distinct processes interact when mapping and retaining labels for novel objects (i.e., low-frequency objects that are unfamiliar to toddlers) via disambiguation from a semantically similar familiar referent in 24-month-olds (N = 65). Toddlers' log-adjusted looking to labeled target objects (relative to distractor objects) was measured in three conditions: Familiar trials (familiar label spoken while viewing semantically related familiar and novel objects), Disambiguation trials (unfamiliar label spoken while viewing semantically similar familiar and unfamiliar object), and Retention trials (unfamiliar label spoken while viewing novel object pairs). Toddlers' individual vocabulary structure was then compared to performance on each condition. Vocabulary structure was measured at two levels: category-level structure (semantic density) for experimental items, and lexicon-level structure (global clustering coefficient). The findings suggest, consistent with prior results, that semantic density interfered with known word recognition, and facilitated unfamiliar word retention. Children did not show a significant novel word preference during disambiguation, and disambiguation behavior was not impacted by semantic structure. These findings connect seemingly disparate mechanisms of semantic interference in processing and semantic leveraging in word learning. Semantic interference momentarily slows word recognition and resolution of referential uncertainty for novel label-object mappings. Nevertheless, this slowing might support retention by enabling comparison between related objects.

Neural Representation of Overlapping Path Segments and Reward Acquisitions in the Monkey Hippocampus

Disambiguation of overlapping events is thought to be the hallmark of episodic memory. Recent rodent studies have reported that when navigating overlapping path segments in the different routes place cell activity in the same overlapping path segments were remapped according to different goal locations in different routes. However, it is unknown how hippocampal neurons disambiguate reward delivery in overlapping path segments in different routes. In the present study, we recorded monkey hippocampal neurons during performance of three virtual navigation (VN) tasks in which a monkey alternately navigated two different routes that included overlapping path segments (common central hallway) and acquired rewards in the same locations in overlapping path segments by manipulating a joystick. The results indicated that out of 106 hippocampal neurons, 57 displayed place-related activity (place-related neurons), and 18 neurons showed route-dependent activity in the overlapping path segments, consistent with a hippocampal role in the disambiguation of overlapping path segments. Moreover, 75 neurons showed neural correlates to reward delivery (reward-related neurons), whereas 56 of these 75 reward-related neurons showed route-dependent reward-related activity in the overlapping path segments. The ensemble activity of reward-related neurons represented reward delivery, locations, and routes in the overlapping path segments. In addition, ensemble activity patterns of hippocampal neurons more distinctly represented overlapping path segments than non-overlapping path segments. The present results provide neurophysiological evidence of disambiguation in the monkey hippocampus, consistent with a hippocampal role in episodic memory, and support a recent computational model of "neural differentiation," in which overlapping items are better represented by repeated retrieval with competitive learning.

Mood Detection in Ambiguous Messages: The Interaction Between Text and Emoticons

Face-to-face communication has several sources of contextual information that enables language comprehension. This information is used, for instance, to perceive mood of interlocutors, clarifying ambiguous messages. However, these contextual cues are absent in text-based communication. Emoticons have been proposed as cues used to stress the emotional intentions on this channel of communication. Most studies have suggested that their role is to contribute to a more accurate perception of emotions. Nevertheless, it is not clear if their influence on disambiguation is independent of their emotional valence and its interaction with text message valence. In the present study, we designed an emotional congruence paradigm, where participants read a set of messages composed by a positive or negative emotional situation sentence followed by a positive or negative emoticon. Participants were instructed to indicate if the sender was in a good or bad mood. With the aim of analyzing the disambiguation process and observing if the role of the emoticons in disambiguation is different according their valence, we measure the rate of responses of perceived mood and the reaction times (RTs) for each condition. Our results showed that the perceived mood in ambiguous messages tends to be more negative regardless of emotion valence. Nonetheless, we observed that this tendency was not the same for positive and negative emoticons. Specifically, negative mood perception was higher for incongruent positive emoticons. On the other hand, RTs for positive emoticons were faster than for the negative ones. Responses for incongruent messages were slower than for the congruent ones. However, the incongruent condition showed different RTs depending on the emoticons' valence. In the incongruent condition, responses for negative emoticons was the slowest. Results are discussed taking into account previous observations about the potential role of emoticons in mood perception and cognitive processing. We concluded that the role of emoticons in disambiguation and mood perception is due to the interaction of emoticon valence with the entire message.

Disambiguate: An open-source application for disambiguating two species in next generation sequencing data from grafted samples

Grafting of cell lines and primary tumours is a crucial step in the drug development process between cell line studies and clinical trials. Disambiguate is a program for computationally separating the sequencing reads of two species derived from grafted samples. Disambiguate operates on DNA or RNA-seq alignments to the two species and separates the components at very high sensitivity and specificity as illustrated in artificially mixed human-mouse samples. This allows for maximum recovery of data from target tumours for more accurate variant calling and gene expression quantification. Given that no general use open source algorithm accessible to the bioinformatics community exists for the purposes of separating the two species data, the proposed Disambiguate tool presents a novel approach and improvement to performing sequence analysis of grafted samples. Both Python and C++ implementations are available and they are integrated into several open and closed source pipelines. Disambiguate is open source and is freely available at https://github.com/AstraZeneca-NGS/disambiguate.

Disambiguate: An open-source application for disambiguating two species in next generation sequencing data from grafted samples

Grafting of cell lines and primary tumours is a crucial step in the drug development process between cell line studies and clinical trials. Disambiguate is a program for computationally separating the sequencing reads of two species derived from grafted samples. Disambiguate operates on DNA or RNA-seq alignments to the two species and separates the components at very high sensitivity and specificity as illustrated in artificially mixed human-mouse samples. This allows for maximum recovery of data from target tumours for more accurate variant calling and gene expression quantification. Given that no general use open source algorithm accessible to the bioinformatics community exists for the purposes of separating the two species data, the proposed Disambiguate tool presents a novel approach and improvement to performing sequence analysis of grafted samples. Both Python and C++ implementations are available and they are integrated into several open and closed source pipelines. Disambiguate is open source and is freely available at https://github.com/AstraZeneca-NGS/disambiguate.

A speaker's gesture style can affect language comprehension: ERP evidence from gesture-speech integration

In face-to-face communication, speech is typically enriched by gestures. Clearly, not all people gesture in the same way, and the present study explores whether such individual differences in gesture style are taken into account during the perception of gestures that accompany speech. Participants were presented with one speaker that gestured in a straightforward way and another that also produced self-touch movements. Adding trials with such grooming movements makes the gesture information a much weaker cue compared with the gestures of the non-grooming speaker. The Electroencephalogram was recorded as participants watched videos of the individual speakers. Event-related potentials elicited by the speech signal revealed that adding grooming movements attenuated the impact of gesture for this particular speaker. Thus, these data suggest that there is sensitivity to the personal communication style of a speaker and that affects the extent to which gesture and speech are integrated during language comprehension.

Temporal dynamics of the knowledge-mediated visual disambiguation process in humans: a magnetoencephalography study

Disambiguation of a noisy visual scene with prior knowledge is an indispensable task of the visual system. To adequately adapt to a dynamically changing visual environment full of noisy visual scenes, the implementation of knowledge-mediated disambiguation in the brain is imperative and essential for proceeding as fast as possible under the limited capacity of visual image processing. However, the temporal profile of the disambiguation process has not yet been fully elucidated in the brain. The present study attempted to determine how quickly knowledge-mediated disambiguation began to proceed along visual areas after the onset of a two-tone ambiguous image using magnetoencephalography with high temporal resolution. Using the predictive coding framework, we focused on activity reduction for the two-tone ambiguous image as an index of the implementation of disambiguation. Source analysis revealed that a significant activity reduction was observed in the lateral occipital area at approximately 120 ms after the onset of the ambiguous image, but not in preceding activity (about 115 ms) in the cuneus when participants perceptually disambiguated the ambiguous image with prior knowledge. These results suggested that knowledge-mediated disambiguation may be implemented as early as approximately 120 ms following an ambiguous visual scene, at least in the lateral occipital area, and provided an insight into the temporal profile of the disambiguation process of a noisy visual scene with prior knowledge.

Fast mapping, slow learning: disambiguation of novel word-object mappings in relation to vocabulary learning at 18, 24, and 30months

When hearing a novel name, children tend to select a novel object rather than a familiar one, a bias known as disambiguation. Using online processing measures with 18-, 24-, and 30-month-olds, we investigate how the development of this bias relates to word learning. Children's proportion of looking time to a novel object after hearing a novel name related to their success in retention of the novel word, and also to their vocabulary size. However, skill in disambiguation and retention of novel words developed gradually: 18-month-olds did not show a reliable preference for the novel object after labeling; 24-month-olds reliably looked at a novel object on Disambiguation trials but showed no evidence of retention; and 30-month-olds succeeded on Disambiguation trials and showed only fragile evidence of retention. We conclude that the ability to find the referent of a novel word in ambiguous contexts is a skill that improves from 18 to 30months of age. Word learning is characterized as an incremental process that is related to - but not dependent on - the emergence of disambiguation biases.