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BACKGROUND Because more than three million children are hospitalized every year in the United States, psychosocial and emotional impacts of hospitalization on children cannot be overlooked. As such, a variety of psychosocial support services are offered in pediatric facilities to reduce the negative effects often associated with hospitalization. This review examines current evidence for the effectiveness of common psychosocial interventions for children and youth undergoing medical procedures. METHODS A total of 34 studies that met selection guidelines, as outlined in Section 2, were included and coded based on study characteristics, intervention type, and study outcomes. RESULTS Findings from this literature review indicate that most studies examining the efficacy of psychosocial interventions reported at least positive outcomes for children. Although the review highlighted an overall pattern for improved outcomes following psychosocial intervention, there were some differences in outcomes based on type of intervention. In general, procedural support, preparation, and coping strategies were associated with reduced child anxiety/fear and distress. Procedural support was commonly associated with reduced pain, although many types of interventions demonstrated reduction in child pain. Procedural support was associated with improved procedural success. CONCLUSIONS This systematic review illustrates the benefits of offering psychosocial interventions, such as procedural support, preparation, teaching coping strategies, and medical play, that support children undergoing medical procedures. There is a need for additional studies that examine psychosocial interventions, including studies that examine long-term outcomes post-procedure or hospitalization. Furthermore, more studies need to collect cost-analysis information specific to the use of psychosocial interventions.

Aim: There are few age‐ and fitness‐specific, evidence‐based guidelines for colorectal cancer surgery. The uptake of different assessment and optimization strategies is variable. The aim of this study was to explore healthcare professional opinion about these issues using a mixed methods design. Methods: Semi‐structured qualitative interviews were undertaken with healthcare professionals from a single UK region involved in the treatment, assessment and optimization of colorectal surgery patients. Interviews were analysed using the framework approach. An online questionnaire survey was subsequently designed and disseminated to UK surgeons to quantitatively assess the importance of interview themes. Descriptive statistics were used to analyse questionnaire data. Results: Thirty‐seven healthcare professionals out of 42 approached (response rate 88%) were interviewed across five hospitals in the south Yorkshire region. Three broad themes were developed: attitudes towards treatment of the older patient, methods of assessment of suitability and optimization strategies. The questionnaire was completed by 103 out of an estimated 256 surgeons (estimated response rate 40.2%). There was a difference in opinion regarding the role of major surgery in older patients, particularly when there is coexisting dementia. Assessment was not standardized. Access to optimization strategies was limited, particularly in the emergency setting. Conclusion: There is wide variation in the process of assessment and provision of optimization strategies in UK practice. Lack of evidence‐based guidelines, cost and time constraints restrict the development of services and pathways. Differences in opinion between surgeons towards patients with frailty or dementia may account for some of the variation in colorectal cancer outcomes.

Background: Adolescents and young adults (AYAs) with cancer use social media in unique ways throughout treatment. The purpose of this article is to describe the social media experiences of AYAs with cancer as a means of exploring the potential impact of social media on AYA psychosocial development after diagnosis and throughout cancer treatment. Methods: Seven AYAs treated for cancer, aged 15–20 years, completed a semi-structured interview regarding their social media preferences and habits. Each interview was transcribed verbatim and de-identified. Data were coded and themes were identified via latent thematic analysis. Results: Four themes emerged regarding social media experiences for AYAs with cancer: (1) changes in audience and feedback after diagnosis; (2) attitudes about body image and peer support; (3) control over personal, familial, and societal messages about illness; and (4) maintaining normalcy despite hospital stressors. Discussion: Social media appear especially useful for promoting social and identity development as AYAs undergo cancer treatment. Specifically, social media provide spaces to negotiate body image and sense of self, to manage peer relationships, to reclaim control and independence, and to maintain normalcy. Understanding these experiences will prepare healthcare providers and caregivers to assess ongoing psychosocial development and adjustment throughout cancer treatment.

Introduction Surgical procedures place children of all ages at risk for pediatric medical traumatic stress. Although medical play has proven effective in pediatric care, little is known about the impacts of a group medical play intervention on children's preoperative fear and anxiety. Therefore, the purpose of this pre-post quasi-experimental study was to explore the relationship between a group medical play activity and children's preoperative fear and anxiety. Method Fifty children (aged 5–10 years) scheduled for a medical procedure participated in a group medical play session facilitated by a Certified Child Life Specialist. Results Statistically significant decreases in anxiety and self-reported fear were observed after the intervention, suggesting that medical play may generate additional coping benefits when offered in group formats. Discussion Providing children with the opportunity to explore and become familiar with medical equipment through group medical play can help to minimize preoperative anxiety and improve the patient experience for children and their families.

BackgroundThe emergence of SARS-CoV-2 triggered a chain of public health responses that radically changed our way of living and working. Non-healthcare sectors, such as the logistics sector, play a key role in such responses. This research aims to qualitatively evaluate the non-pharmaceutical interventions (NPIs) implemented in the UK logistics sector during the COVID-19 pandemic.MethodsWe conducted nine semi-structured interviews in July-August 2020 and May-June 2021. In total 11 interviewees represented six companies occupying a range of positions in the UK's logistics sector, including takeaway food delivery, large and small goods delivery and home appliance installation, and logistics technology providers. Thematic analysis was completed using NVivo12. Codes relevant to NPIs were grouped into themes and mapped deductively onto an adapted Hierarchy of Control (HoC) framework, focusing on delivery workers. Codes relevant to the implementation process of NPIs were grouped into themes/subthemes to identify key characteristics of rapid responses, and barriers and facilitators.ResultsHoC analysis suggests the sector has implemented a wide range of risk mitigation measures, with each company developing their own portfolio of measures. Contact-free delivery was the most commonly implemented measure and perceived effective. The other implemented measures included social distancing, internal contact tracing, communication and collaboration with other key stakeholders of the sector. Process evaluation identified facilitators of rapid responses including capacity to develop interventions internally, localized government support, strong external mandates, effective communication, leadership support and financial support for self-isolation, while barriers included unclear government guidance, shortage of testing capacity and supply, high costs and diversified language and cultural backgrounds. Main sustainability issues included compliance fatigue, and the possible mental health impacts of a prolonged rapid response.ConclusionsThis research identified drivers and obstacles of rapid implementation of NPIs in response to a respiratory infection pandemic. Existing implementation process models do not consider speed to respond and the absence or lack of guidance in emergency situations such as the COVID-19. We recommend the development of a rapid response model to inform the design of effective and sustainable infection prevention and control policies and to focus future research priorities.

Background Workplace transmission is a significant contributor to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) outbreaks. Previous studies have found that infectious illness presenteeism could contribute to outbreaks in occupational settings and identified multiple occupational and organisational risk factors. Amid the COVID-19 pandemic, it is imperative to investigate presenteeism particularly in relation to respiratory infectious disease (RID). Hence, this rapid review aims to determine the prevalence of RID-related presenteeism, including COVID-19, and examines the reported reasons and associated risk factors. Methods The review followed a Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) search approach and focused on studies published in English and Chinese. Database searches included MEDLINE, EMBASE, Web of Science, China Knowledge Resource Integrated Database (CNKI) and preprint databases MedRxiv and BioRxiv. Results The search yielded 54 studies, of which four investigated COVID-19-related presenteeism. Prevalence of work presenteeism ranged from 14.1 to 55% for confirmed RID, and 6.6 to 100% for those working with suspected or subclinical RID. The included studies demonstrated that RID-related presenteeism is associated with occupation, sick pay policy, age, gender, health behaviour and perception, vaccination, peer pressure and organisational factors such as presenteeism culture. Conclusions This review demonstrates that presenteeism or non-adherence to isolation guidance is a real concern and can contribute to workplace transmissions and outbreaks. Policies which would support workers financially and improve productivity, should include a range of effective non-pharmaceutical inventions such as workplace testing, promoting occupational health services, reviewing pay and bonus schemes and clear messaging to encourage workers to stay at home when ill. Future research should focus on the more vulnerable and precarious occupational groups, and their inter-relationships, to develop comprehensive intervention programs to reduce RID-related presenteeism.

IntroductionPrehabilitation in colorectal surgery is evolving and may minimise postoperative morbidity and mortality. With many different healthcare professionals contributing to the prehabilitation literature, there is significant variation in reported primary endpoints that restricts comparison. In addition, there has been limited work on patient-related outcome measures suggesting that patients with colorectal cancer needs and issues are being overlooked. The Defining Standards in Colorectal Optimisation Study aims to achieve international consensus from all stakeholders on key standards to provide a framework for reporting future prehabilitation research.Methods and analysisA systematic review will identify key standards reported in trials of prehabilitation in colorectal surgery. Standards that are important to patients will be identified by a patient and public involvement (PPI) event. The longlist of standards generated from the systematic review and PPI event will be used to develop a three-round online Delphi process. This will engage all stakeholders (healthcare professionals and patients) both nationally and internationally. The results of the Delphi will be followed by a face-to-face interactive consensus meeting that will define the final standards for prehabilitation for elective colorectal surgery.Ethics and disseminationThe University of Glasgow College of Medical, Veterinary and Life Sciences Ethics Committee has approved this protocol, which is registered as a study (200190120) with the Core Outcome Measures in Effectiveness Trials Initiative. Publication of the standards developed by all stakeholders will increase the potential for comparative research that advances understanding of the clinical application of prehabilitation.PROSPERO registration numberCRD42019120381.

Introduction: National datasets report large variations in outcomes from older people (≥65 years) between different UK surgical units. This implies that not all patients receive the same level of care or access to resources, such as rehabilitation or allied health professional input. This might impact functional decline. Aims: Our aim is to evaluate the baseline status of older patients facing major gastrointestinal surgery and the impact of variation in perioperative assessment and provision of perioperative support on functional outcomes. Patients’ experiences and views of assessment and optimization will be explored via integrated qualitative semi-structured interviews. Methods and analysis: This multi-centre, pilot cohort study will include patients ≥65 years presenting via both elective and emergency pathways at three to five South Yorkshire NHS hospitals (Clinical Trials registration NCT04545125). The primary outcome is functional recovery measured using the World Health Organization Disability Assessment Schedule 2.0 at 6 weeks post-operation. Secondary outcomes include feasibility, quality of life, length of stay and complication rate. An opportunistic sample size of 120 has been estimated and will inform the design of a future, adequately powered study. For the qualitative study, 20–30 semi-structured patient interviews will be undertaken with patients from the cohort study to explore experiences of assessment and optimization. Interviews will be digitally recorded, transcribed verbatim and analysed according to the framework approach. Ethics and dissemination: This study has been approved by the National Health Service Research Ethics Committee and is registered centrally with Health Research Authority. It has been adopted by the National Institute for Health Research Portfolio scheme. Dissemination will be via international and national surgical and geriatric conferences.

Clinical Scenario: Therapeutic ultrasound (US) is a popular modality among health care professionals and is used to treat a variety of musculoskeletal conditions. A new technology has been established to allow for the miniaturization of the US unit. Patients receive treatment with the device secured to them, eliminating the portability constraint of traditional US units. Early studies suggest that this portable unit can deliver low-intensity acoustic energy achieving the same temperature increase and pain relief that come from traditional US units, in a more versatile and patient-friendly manner. Clinical Question: What effects does low-intensity therapeutic ultrasound (LITUS) have on measurable outcomes? Summary of Key Findings: The literature was searched for level 4 evidence or higher that investigated the effectiveness of LITUS. The literature search produced 3 possible studies related to the clinical question: 2 randomized controlled trials and 1 case series met the inclusion and exclusion criteria. Of the included studies, 1 study investigated the effects of LITUS on tissue temperature, 2 studies investigated the effects of LITUS on pain, and 1 study investigated LITUS effects on function. Clinical Bottom Line: The evidence supports the use of the LITUS unit to increase tissue temperature, decrease pain, and increase function. Therefore, practitioners may consider the use of the LITUS unit in patient populations over the use of the traditional high-intensity US treatment. Strength of Recommendation: In accordance with the 2009 Centre for Evidence-Based Medicine levels of evidence, there is grade I (insufficient) evidence to support the positive effects of the LITUS device for improving the following clinical outcomes: tissue temperature, decreasing pain, and increasing function. The inconsistency in the measured outcomes across the 3 studies only allows for minimal support of the LITUS device, warranting further research. Although clinical outcomes were different in each study, consistent evidence ranging from 4 to 1B levels were found in the 3 included studies.

Although pain is one of the most prevalent and bothersome symptoms children with cancer experience, evidence-based guidance regarding assessment and management is lacking. With 44 international, multidisciplinary healthcare professionals and nine patient representatives, we aimed to develop a clinical practice guideline (following GRADE methodology), addressing assessment and pharmacological, psychological, and physical management of tumor-, treatment-, and procedure-related pain in children with cancer. In this paper, we present our thorough methodology for this development, including the challenges we faced and how we approached these. This lays the foundation for our clinical practice guideline, for which there is a high clinical demand.

Ischaemic colitis is an infrequent but serious complication following repair of abdominal aortic aneurysm (AAA), with high mortality rates. This systematic review set out to identify risk factors for the development of ischaemic colitis after AAA surgery. A systematic search of the MEDLINE, EMBASE and CINAHL databases was performed. This search was limited to studies published in the English language after 1990. Abstracts were screened by two authors. Eligible studies were obtained as full text for further examination. Data was extracted by two authors, and any disputes were resolved via consensus. Extracted data was pooled using Mantel-Haenszel random effects models. Bias was assessed using two Cochrane-approved tools. Effect sizes are expressed as relative risk ratios alongside the 95 % confidence interval. Statistical significance was defined at the level of p

Background: Readmission rates after surgical procedures are viewed as a marker of quality of care and as a driver to improve outcomes in the United Kingdom, they are not remunerated. However, readmissions are not wholly avoidable. The aim of this study was to develop a regional overview of readmissions to determine the proportion that might be avoidable and to examine predictors of readmissions at a unit level. Methods: We undertook a prospective multicenter audit of readmissions following National Health Service funded general surgical procedures in five National Health Service hospitals and three independent sector providers over a 2-wk period. Basic demographic and procedure data were captured. Readmissions to hospitals were identified through acute admissions lists. Reason for readmission was identified, and the readmission data assessed by a senior surgical doctor as to whether it was avoidable. Results: We identified 752 operations in the study period with all followed up to 30 d. The overall rate of readmissions was 4.7%, with 40% of these judged as being potentially avoidable. Pain and wound problems accounted for the vast majority of avoidable readmissions. The number of unavoidable readmissions was correlated with the workload of each center (r ¼ 0.63, P ¼ 0.06) and as with the higher (British United Provident Association) complexity of surgery (r ¼ 0.90, P ¼ 0.01). Patient and demographic factors were not associated with readmissions. Conclusions: This prospective audit describes readmission rates after general surgery. Volume and complexity of work are associated with readmission rates. A large proportion of readmissions could be reduced by attention to analgesia and outpatient arrangements for wound management.

Introduction Recent studies have suggested that laparoscopic surgery for colorectal resection confers a cost benefit compared with open surgery. These studies have considered a wide range of colorectal operations together rather than focusing on a single procedure. Our study compared direct clinical costs for laparoscopic versus open right hemicolectomy. Methods Clinicopathological data and cost of treatment for all patients who underwent a right hemicolectomy between 2012 and 2013 were collected. The primary outcome was total cost of treatment. Secondary outcomes were length of stay, operative time and morbidity. The minimum follow-up duration was 12 months. Costs for laparoscopic and open surgery for elective resection alone were compared. Further analyses were performed comparing emergency cases with elective cases and cancer with non-cancer cases. Results There were 83 patients who underwent a right hemicolectomy during the study period and of these, 65 had an elective procedure. The total cost of a laparoscopic procedure was £3,998.12 compared with £3,427.50 for open surgery (p=0.039). The length of stay was shorter for laparoscopic surgery while the cost of an emergency right hemicolectomy was significantly greater than for elective surgery. Conclusions Although the length of stay for laparoscopic surgery was shorter, this did not translate to a reduction in cost. The cost benefit from a shorter length of stay was offset by a greater cost of consumables. Cost effectiveness analyses should be designed carefully, and they should consider individual operations separately when making healthcare management and funding decisions.

Objective This study aims to explore the views of members of theater teams regarding the proposed introduction of a workplace-based assessment of nontechnical skills of surgeons (NOTSS) into the Intercollegiate Surgical Curriculum Programme in the United Kingdom. In addition, the previous training and familiarity of the members of the surgical theater team with the concept and assessment of NOTSS would be evaluated. Design A regional survey of members of theater teams (consultant surgeons, anesthetists, scrub nurses, and trainees) was performed at 1 teaching and 2 district general hospitals in South Yorkshire. Results There were 160 respondents corresponding to a response rate of 81%. The majority (77%) were not aware of the NOTSS assessment tool with only 9% of respondents reporting to have previously used the NOTSS tool and just 3% having received training in NOTSS assessment. Overall, 81% stated that assessing NOTSS was as important as assessing technical skills. Trainees attributed less importance to nontechnical skills than the other groups (p ≤ 0.016). Although opinion appears divided as to whether the presence of a consultant surgeon in theater could potentially make it difficult to assess a trainee's leadership skills and decision-making capabilities, overall 60% agree that the routine use of NOTSS assessment would enhance safety in the operating theater and 80% agree that the NOTSS tool should be introduced to assess the nontechnical skills of trainees in theater. However, a significantly lower proportion of trainees (45%) agreed on the latter compared with the other groups (p = 0.001). Conclusions Our survey demonstrates acceptability among the theater team for the introduction of the NOTSS tool into the surgical curriculum. However, lack of familiarity highlights the importance of faculty training for assessors before such an introduction.

This article aims to uncover the extent to which convenience foods have become embedded in today's diets. The paper focuses on households' food expenditures, collected by Statistics Belgium in 2005. The results show that households' reliance on (semi-) convenience food items and away-from-home consumption clearly differs over the life-course and amongst different social groups. Findings show that single-living households (single men in particular) look for more convenience in their food preparation patterns compared to couples and households with children. The consumption of semi-convenient meal components seems to be more closely related to the conventional definition of home-cooking, with older-generation, lower-educated, non-working and ‘traditional’ nuclear households being more likely to spend a larger share of their food budget on non-convenient and ‘shortcut’ ingredients.

Previous reports of cognitive functioning in children with the 22q11 Deletion Syndrome have reported marked variability in IQ and achievement subtest scores. Studies have begun to explore neuropsychological function in 22q11 DS however results are inconsistent and the profile incomplete. We assessed 40 children ages 5–12 with 22q11 DS. Consistent with past results, visual-spatial memory was significantly lower than verbal memory. Differentially lowered scores were found only in visual attention, working memory and motor function. Contrary with some past results quantitative, verbal ability, and visual spatial memory scores were within 1 SD from the standardization sample mean. Motor behavior, not typically discussed with regard to 22q11 DS school-age children, may be critical to incorporate in neurocognitive studies of children with 22q11 DS. Implications of these findings are considered with regard to past results.

The 22q11 chromosomal deletion syndrome (22q11 DS) is associated with learning disabilities and a complex neuropsychological profile. Previous findings have suggested that executive attention deficits might underlie other neurocognitive anomalies. We administered the child Attention Network Test (ANT) to 52 children ages 5.0 to 11.5, 32 22q11 DS children (19 girls) and 20 controls (13 girls) and assessed the efficiency of segregated executive, orienting, and alerting networks. We hypothesized that 22q11 DS children have impaired executive network efficiency as compared to control siblings. The internal validity of the child ANT was confirmed for this population. Analysis of variance results showed significant main effects for flanker and cue types and no interaction effect in either 22q11 DS children or control siblings. Compared to control siblings, 22q11 DS children had significantly larger (less efficient) executive network scores, significantly increased errors on only incongruent trials, and a significant correlation between executive network scores and accuracy. The implications of these findings for future neurocognitive studies of 22q11 DS children are considered.

Objective: To determine whether estrogen therapy at the time of coronary artery bypass grafting affects postoperative complications. Methods: Consecutive postmenopausal women who had coronary artery bypass grafting between 1992 and 1997 were identified and their medical records were reviewed. Outcome measures included mortality, perioperative cardiac morbidity, and early and late postoperative complications. Results: Estrogen therapy was noted in 13.9% of 734 women. Those using estrogen replacement were younger (63.9 ± 0.27 versus 68.8 ± 0.64 years) and had higher ejection fractions (2.8 ± 0.11 versus 3.1 ± 0.04) and fewer vessels bypassed. Mortality rates were 2.9% for estrogen users and 7.4% for nonusers (odds ratio [OR] 0.38; confidence interval [CI] 0.07, 1.21). Perioperative cardiac morbidity rates were 5.8% for estrogen users and 11% for nonusers (OR 0.52; CI 0.23, 1.7). Early complication rates were 0.98% for estrogen users and 1.11% for nonusers. Late inpatient complications were noted in 6.8% of treated women and 14.8% of those untreated (OR 0.42; CI 0.16, 0.96). Stepwise logistic regression confirmed age, New York Heart Association angina classification, and ejection fraction as significant variables for mortality, perioperative cardiac morbidity, and late complications. Estrogen therapy did not influence mortality, perioperative cardiac morbidity, or early or late complications. Conclusion: Age, ejection fraction, and New York Heart Association angina classification predicted mortality, perioperative cardiac morbidity, and late complications. Estrogen therapy at the time of admission for coronary artery bypass grafting did not influence surgical mortality, perioperative cardiac morbidity, or early or late complications.

One of the most fundamental, but also controversial, food trends of the past years is convenience food. This article investigates the underexplored relationship between the heterogeneity in (convenience) food consumption (a feature of a food culture's cuisine) and meal patterns (characteristics of a food culture's structure). This study hopes to illustrate that convenience food can be interpreted both as a means to maintain a food culture's structure and as a means to overturn it. Latent Class Cluster Analysis is performed using data from the HBS 2005 survey on families' food expenditures to conceptualize convenience-orientation and to examine the relationships with families' meal behaviors. Whereas outsourcing cooking is most prevalent among single-person households; two-or more-person households are most likely to buy unprocessed and natural foods and to spend most time cooking and eating in. A higher consumption of convenience food is also more likely to affect individuals' kitchen than table habits.

Cooking is one of the basic activities in our lives. However, people frequently feel they fall short of time to cook when facing problems with the temporal organization of daily life. How people think about home cooking is considered to be important for the time they spend on preparing meals. It is assumed that the meaning of cooking differs for different people, depending on the temporal and social context. This contribution allows us to clarify how the meaning of cooking varies according to individual and household characteristics and the cooking occasion. By using the pooled time-diary data from the Flemish time-use surveys from 1999 and 2004 we can examine people's views on cooking in order to understand how people use time for food preparation. Although the results suggest that people consider cooking primarily as a household chore, preparing food can also be a way to please others, as well as themselves. It seems that feelings of time pressure and the family situation are clearly related to men's and women's cooking experiences. Furthermore, the meaning of cooking also tends to be clearly influenced by the meal situation and (the moment of) the day.

Disruption of the long-range cis-regulation of developmental gene expression is increasingly recognized as a cause of human disease. Here, we report a novel type of long-range cis-regulatory mutation, in which ectopic expression of a gene is driven by an enhancer that is not its own. We have termed this gain of regulatory information as “enhancer adoption.” We mapped the breakpoints of a de novo 7q inversion in a child with features of a holoprosencephaly spectrum (HPES) disorder and severe upper limb syndactyly with lower limb synpolydactyly. The HPES plausibly results from the 7q36.3 breakpoint dislocating the sonic hedgehog (SHH) gene from enhancers that are known to drive expression in the early forebrain. However, the limb phenotype cannot be explained by loss of known SHH enhancers. The SHH transcription unit is relocated to 7q22.1, ∼190 kb 3′ of a highly conserved noncoding element (HCNE2) within an intron of EMID2. We show that HCNE2 functions as a limb bud enhancer in mouse embryos and drives ectopic expression of Shh in vivo recapitulating the limb phenotype in the child. This developmental genetic mechanism may explain a proportion of the novel or unexplained phenotypes associated with balanced chromosome rearrangements. 32:1492–1499, 2011. ©2011 Wiley Periodicals, Inc.

The study examined factors in deaf parents' decision between cochlear implantation (CI) and traditional hearing aids for their child. The subjects were 6 Flemish children ages 5-9 years with severe/profound congenital hearing loss, with at least 1 deaf parent. The researchers, who conducted thematic content analysis of qualitative data collected through parent interviews, found that with the exception of a family with 1 hearing parent, parents gave priority to Deaf identity, sign language, and ethical issues in deciding between CI and hearing aids. Medical risks were also mentioned. The researchers conclude that the decision-making processes of the parents involved factors that have also been found among hearing parents, as well as aspects that have not been reported to play a role in hearing parents' decision making. A further conclusion is that deaf parents' perspective merits attention in professional practice and empirical research.