B B Toner

University of North Carolina at Chapel Hill, Chapel Hill, NC, United States

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Publications (80)380.3 Total impact

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    ABSTRACT: For clinical trials in functional bowel disorders (FBD), the definition of a responder, one who meets the predefined criteria for a clinical response, is needed. Factors that determine clinical response aside from treatment itself are unknown. The aim of this study was to determine what baseline and post-treatment factors affect treatment response. Females (n=397) with FBD entering a 12-week, four-arm, randomized NIH treatment trial (desipramine (DES), CBT, pill placebo, and education) were studied at baseline and after treatment. Demographic, clinical, psychosocial, and physiological variables were considered in the analysis. A responder was defined as a patient obtaining a score>3.5 on an averaged eight-item, five-point satisfaction-with-treatment questionnaire. Baseline and post-treatment logistic regressions were performed for each treatment condition to predict the responder outcome variable. Similar cognitive features predisposed participants to treatment response across the treatment conditions: sense of control over the condition, positive relationship with therapist or study coordinator, confidence in treatment, improvement in maladaptive cognitions, and quality of life during treatment. Demographic and clinical variables studied were not predictive. Some treatment-specific effects predicting responder status were noted, including a reduction in stool frequency with DES treatment and lack of abuse history in the placebo group. For medication, psychological, and placebo treatment in FBD, satisfaction with treatment depends on cognitive factors of confidence in treatments, perceived control over illness and symptoms, and reduction in negative cognitions related to symptom experience. Addressing these issues among patients with FBD may enhance treatment response to a variety of treatments.
    The American Journal of Gastroenterology 06/2010; 105(6):1397-406. · 7.55 Impact Factor
  • Gastroenterology 01/2010; 138(5). · 12.82 Impact Factor
  • Gastroenterology 01/2010; 138(5). · 12.82 Impact Factor
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    ABSTRACT: The implications of the Rome III recommendations to change the irritable bowel syndrome (IBS) subtype criteria for stool pattern are unknown. (1) Determine the level of agreement between Rome II and Rome III subtypes and (2) compare the behaviors of Rome II and Rome III subtypes over time. Female patients (n=148) with Rome II defined IBS were prospectively tracked over 5 consecutive 3-month periods. At baseline, bowel habit reports on questionnaires were used to subclassify patients into Rome II and Rome III subtypes. Over the subsequent 15 months, bowel habit reports on diary cards were used to subclassify patients based on previously derived surrogate criteria into Rome II and Rome III IBS subtypes. The level of agreement between Rome II and Rome III subtype assignments was quite high (86.5%; kappa 0.79). The behavior of Rome II and Rome III subtypes over time was also similar in terms of subtype prevalence, subtype stability, and the proportion of subjects who met criteria for alternating irritable bowel syndrome. Rome II and Rome III IBS subtypes are in high agreement and behave similarly over time. Therefore, studies that used Rome II subtype criteria and studies that will use Rome III criteria will define comparable populations.
    Journal of clinical gastroenterology 04/2009; 43(3):214-20. · 2.21 Impact Factor
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    ABSTRACT: Patients with functional gastrointestinal disorders treated with tricyclic antidepressants sometimes report nongastrointestinal symptoms; it is unclear whether these are drug side effects or reflect a behavioral tendency to report symptoms. We evaluated whether symptoms reported before treatment with a tricyclic antidepressant (desipramine) increased in number or worsened in severity after 2 weeks of treatment and assessed the baseline factors that predispose patients to report symptoms. Female patients in a multicenter National Institutes of Health trial for functional bowel disorders completed a 15-item symptom questionnaire at baseline (before randomization), 2 weeks after they were given desipramine (n = 81) or placebo (n = 40), and at study completion (12 weeks). Patients were asked about the severity and frequency of 15 symptoms. Results were analyzed from 57 patients given desipramine who completed the questionnaires. Symptoms reported as side effects to have occurred more frequently and also worsened at week 2 in the group given desipramine included dizziness, dry mouth/thirstiness, lightheadedness, jittery feelings/tremors, and flushing. Symptoms that did not change in severity or showed improvement at week 2 in the group given desipramine included morning tiredness, nausea, blurred vision, headaches, appetite reduction, and trouble sleeping. Psychologic distress but not desipramine blood level correlated with symptom reporting. Most symptoms often attributed to side effects of desipramine were present before treatment; only a few, related to anticholinergic effects, worsened 2 weeks after treatment, suggesting that most so-called side effects were not associated specifically with desipramine use. Such symptoms might instead be associated with psychologic distress.
    Clinical gastroenterology and hepatology: the official clinical practice journal of the American Gastroenterological Association 11/2008; 7(4):446-51. · 5.64 Impact Factor
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    ABSTRACT: To examine the presence and nature of disordered eating attitudes and behaviours among Jewish Canadian adolescents, as compared with non-Jewish Canadian adolescents in an urban community. A secondary goal was to examine whether rates of eating-disordered behaviour differed among the adolescents based on the degree of Jewish religious observance. High school students (n = 868) from the Toronto area completed a demographic and religious practice questionnaire together with the Eating Attitudes Test (EAT), a self-report test that discriminated adolescents with syndromal eating disorders from normal adolescents. Jewish females aged 13 to 20 years, but not males, reported significantly more disordered eating behaviours and attitudes, compared with their non-Jewish female counterparts. Twenty-five percent of Jewish females, as compared with 18% of non-Jewish females, scored above the clinical cut-off for the EAT. No differences in vulnerability to disordered eating were found within the group of Jewish females or males related to their degree of religious observance. Adolescent Jewish females, but not males, appear to be at greater risk for abnormal attitudes and behaviours related to eating, compared with their non-Jewish female peers. While the reasons for this finding are unclear, this study is a step toward improving understanding of the relations between sex, culture, religion, and the development of eating disorders. Culturally sensitive and sex-specific prevention strategies and treatment interventions are indicated.
    Canadian journal of psychiatry. Revue canadienne de psychiatrie 10/2008; 53(9):601-8. · 2.48 Impact Factor
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    ABSTRACT: There has been some question about the classification of painful constipation (PC) and its relationship to irritable bowel syndrome (IBS), and in particular IBS with constipation (IBS-C). We sought to: (1) compare PC with IBS and its subtypes (IBS-C, IBS-D, and IBS-A) in terms of pain scores, stool habit and clinical features, and to determine which factors predict PC over IBS, (2) determine the variation in pain and stool habit for PC relative to IBS over time, and (3) compare whether there are clinical differences between those with high pain constipation (HPC) and low pain constipation (LPC) over time. Among 231 women in an National Institutes of Health trial, Rome II moderate to severe PC (n=41), IBS-A (n=55), IBS-C (n=80), and IBS-D (n=55) received diary cards on stool frequency, consistency, and pain (visual analog scale) daily for 14 days before and after 12-week treatment and at 3-month intervals for 1 year. PC was characterized into HPC (high pain) and LPC (low pain) groups based on visual analog scale pain scores (high pain > or = 50 and low pain < 50) at baseline. Descriptive statistics were calculated, and comparisons performed by chi2 for categorical and t tests for continuous variables. Regressions and repeated measures tested between group and within-group associations, respectively. (a) PC is different from IBS with: higher pain scores (P=0.002), lower education (P=0.02), greater healthcare use and surgeries (P=0.05 to 0.003), and poorer daily function (Sickness Impact Profile overall P=0.004), (b) PC is similar to IBS-C and IBS-A but different from IBS-D for stool frequency and consistency (P<0.0001), bloating (P=0.02), laxative/antidiarrheal use (P=0.04 and 0.02), and lower education (P=0.02). (c) Over 1 year, PC: maintained higher pain scores than IBS, had stool frequencies less than IBS-D and between IBS-C and IBS-A, had stool consistency less than IBS-D and similar to IBS-A, (d) for HPC and LPC there was no difference in constipation, and HPC switched to LPC over time, while LPC pain scores stayed low. Limitations include the absence of a painless constipation group, and that studying moderate to severe symptoms, which may not represent all with PC or IBS. PC is clinically similar in stool pattern and bloating to IBS-C and IBS-A, but with greater pain, healthcare utilization, and poorer daily function. The findings also suggest that PC defines a population where there is greater pain, and poorer health status and daily function, which may be driven more by visceral and/or central pain dysregulation more than the constipation.
    Journal of clinical gastroenterology 01/2008; 42(10):1080-8. · 2.21 Impact Factor
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    ABSTRACT: Hereditary non-polyposis colorectal cancer (HNPCC) represents about 1-3% of all cases of colorectal cancer (CRC). The objectives of the study were to examine motivational factors, expectations and psychosocial functioning in a sample of CRC survivors undergoing genetic testing for HNPCC. A cross-sectional survey of 314 colorectal cancer patients recruited through a population-based colon cancer family registry was conducted. Motivations for genetic testing for hereditary cancer were similar to those of clinic-based samples of CRC patients and included learning of the increased risk to offspring and finding out if additional screening was needed. While age at diagnosis and sex were associated with psychological functioning, significant predictors of post-counseling distress were perceived lower satisfaction with social support, an escape-avoidant coping style and the anticipation of becoming depressed if a mutation was present. Most cancer survivors anticipated disclosing test results to relatives and physicians. Cancer survivors reported several motivations for genetic testing for HNPCC that varied by sex. A subgroup of survivors with lower satisfaction with social support and an escape-avoidant coping style were worried about the potential impact of genetic test results and demonstrated more distress following counseling. Findings have implications for future research and potential support needs during the genetic counseling and testing process.
    Clinical Genetics 12/2007; 72(5):394-401. · 3.94 Impact Factor
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    Taryn N Tang, Keith Oatley, Brenda B Toner
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    ABSTRACT: This study examined the life events and difficulties inherent to the immigration process and the sources of social support that influenced mental health. A six-month longitudinal study, utilizing a detailed semi-structured interview protocol and standardized questionnaires, was conducted with a group of Chinese women who had migrated to Canada with their spouses in the last decade. All of the women and all of their spouses experienced major downward mobility. Correspondingly, the most frequent negative life event was employment-related and the most frequent difficulty was the financial strain of living below the poverty line, factors which significantly predicted the women's mental health. Social support had neither a main effect on mental health nor a buffer effect on the relationship between life events and difficulties and mental health. Implications for immigration and settlement policy are discussed.
    Journal of Immigrant and Minority Health 11/2007; 9(4):281-90. · 1.16 Impact Factor
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    ABSTRACT: Assessing health related quality of life (HRQOL) is becoming more important in research and clinical care. However, little information is available on the performance of HRQOL questionnaires for the functional bowel disorders (FBD). The aims of this study were to (a) understand the performance of the Sickness Impact Profile (SIP) and IBS-QOL for the functional bowel disorders at baseline and after treatment, (b) determine which HRQOL subscales best improve with treatment, (c) determine clinically meaningful improvement, and (d) determine the predictors of HRQOL at baseline and in response to treatment. Women with moderate to severe FBD were evaluated using both medical (desipramine vs placebo) and psychological (cognitive-behavioral therapy vs education) treatments. Clinical and psychosocial questionnaires along with the SIP and IBS-QOL were given at baseline and after 12-wk treatment. (a) Patients with FBD experience functional limitations in social interactions, home management, and recreational activities, respond emotionally to the pain, feel helpless, out of control, depressed, and irritable, and perceive restrictions in lifestyle relating to toilet accessibility, and eating; (b) HRQOL is not different among the FBD diagnoses or IBS subgroups; (c) the IBS-QOL is more responsive to treatment than the SIP; (d) meaningful clinical improvement is 2.8 points for SIP and 14 for IBS-QOL; and (e) improvement is demonstrated primarily in psychosocial rather than physical domains. In addition, we found that expectation of benefit is greater for taking a pill over a psychological intervention, and the predictive effects of abuse history and pain on outcome is mediated by psychosocial factors. The data support the value of the IBS-QOL over the SIP, and provide new information on the profile of impairment in FBD, and the ways in which medical and psychological treatments produce improvement in HRQOL.
    The American Journal of Gastroenterology 08/2007; 102(7):1442-53. · 7.55 Impact Factor
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    ABSTRACT: Patients with functional gastrointestinal disorders (FGID) often experience emotional distress, a perceived lack of validation, and an unsatisfactory experience with health care providers. A health care provider can provide the patient with a framework in which to understand and legitimize their symptoms, remove self-doubt or blame, and identify factors that contribute to symptoms that the patient can influence or control. This framework can be strengthened with the consideration of various important factors that impact FGID but are often overlooked. These include gender, age, society, culture, and the patient's perspective. There is evidence for sex- and gender-related differences in FGID, particularly irritable bowel syndrome (IBS). Whereas the majority of FGID, including IBS, bloating, constipation, chronic functional abdominal pain, and pelvic floor dysfunction, are more prevalent in women than men, functional esophageal and gastroduodenal disorders do not appear to vary by gender. Limited studies suggest that sex differences in visceral perception, cardioautonomic responses, gastrointestinal motility, and brain activation patterns to visceral stimuli exist in IBS. Gender differences in social factors, psychological symptoms, and response to psychological treatments have not been adequately studied. However, there appears to be a greater clinical response to serotonergic agents developed for IBS in women compared to men. The impact of social and cultural factors on the meaning, expression, and course of FGID are important. The prevalence of IBS appears to be lower in non-Western than Western countries. Although further studies are needed, the existing literature suggests that they are important to consider from both research and clinical perspectives.
    Gastroenterology 05/2006; 130(5):1435-46. · 12.82 Impact Factor
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    Brenda B Toner
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    ABSTRACT: There is increasing evidence that supports the view that irritable bowel disorder (IBS) is a disorder of brain-gut function. Cognitive-behavioral therapy (CBT) has received increased attention in light of this recent shift in the conceptualization of IBS. This review has two main aims. The first is to provide a critical review of controlled trials on CBT for IBS. The second is to discuss ways of further developing CBT interventions that are more clinically relevant and meaningful to health care providers and individuals with a diagnosis of IBS. A theme from a CBT intervention will be presented to illustrate how CBT interventions can be incorporated within a larger social context. A review of CBT for IBS lends some limited support for improvement in some IBS symptoms and associated psychosocial distress. This conclusion needs to be expressed with some caution, however, in light of many methodological shortcomings including small sample sizes, inadequate control conditions and failure to identify primary versus secondary outcome measures. In addition, future studies will need to further develop more relevant CBT protocols that more fully integrate the patient's perspective and challenge social cognitions about this stigmatized disorder.
    CNS spectrums 12/2005; 10(11):883-90. · 1.73 Impact Factor
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    ABSTRACT: As shown in the per protocol analysis of a recent randomized, controlled trial, when tolerated, Desipramine (DES) is effective over placebo (PLA) in treating moderate-to-severe functional bowel disorders (FBD). Clinical experience suggests that the benefit from tricyclic antidepressants (TCA) in FBD can be achieved at doses lower than those used to treat major depression. Within psychiatry, when using higher dosage of TCAs, plasma levels can be used to adjust daily dosage to optimize a treatment response. However, in FBD, it is not known whether plasma levels at the lower dosage are similarly related to a clinical response. To determine in treating FBD, whether DES blood levels or dose taken can predict a clinical response. As part of a study of 12 wk of antidepressant and psychological treatment in 431 patients with FBD at UNC and U of Toronto, we studied those participants who completed treatment (per protocol analysis) taking DES (N = 97, dose 50-150 mg/day) or pill placebo (PLA) (N = 55 1-3 pills/day). The primary outcome measure was defined as a composite score (Satisfaction with Treatment, McGill Pain Questionnaire, Global Well-being, and IBS-QOL). The composite score was correlated with: (i) DES plasma levels at week 6, and (ii) number of pills taken over the duration of the 12-wk treatment period. In addition, we also compared DES dose with DES plasma levels. There was a modest correlation between mean DES dose at weeks 5 and 6 and DES blood level at week 6 (R = 0.2 p < 0.07). However, there were no significant correlations between the composite score either with DES dose or with DES blood levels. Detectable blood levels of DES are associated with a clinical response in FBD. However, with dosages up to 150 mg, there is no relationship between total dose or plasma level and the clinical response.
    The American Journal of Gastroenterology 04/2005; 100(3):664-71. · 7.55 Impact Factor
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    ABSTRACT: Irritable bowel syndrome (IBS) is subtyped as IBS with diarrhea (IBS-D) or IBS with constipation (IBS-C) based on Rome II guidelines. The remaining group is considered as having mixed IBS (IBS-M). There is no standard definition of an alternator (IBS-A), in which bowel habit changes over time. Our aim was to use Rome II criteria to prospectively assess change in bowel habit for more than 1 year to understand IBS-A. Female patients (n=317) with IBS entering a National Institutes of Health treatment trial were studied at baseline with questionnaires and 2-week daily diary cards of pain and stool frequency and consistency. Studies were repeated at the end of treatment (3 months) and at four 3-month intervals for one more year. Algorithms to classify subjects into IBS-D, IBS-C, and IBS-M groups used diary card information and modified Rome II definitions. Changes in bowel habit at 3-month intervals were then assessed using these surrogate diary card measures. At baseline, 36% had IBS-D, 31% IBS-M, and 34% IBS-C. Except for stool frequency, there were no differences between groups. While the proportion of subjects in each subgroup remained the same over the year, most individuals (more than 75%) changed to either of the other 2 subtypes at least once. IBS-M was the least stable (50% changed out by 12 weeks). Patients were more likely to transition between IBS-M and IBS-C than between IBS-D and IBS-M. Notably, only 29% switched between the IBS-D and IBS-C subtypes over the year. While the proportion of subjects in each of the IBS subtypes stays the same, individuals commonly transition between subtypes, particularly between IBS-M and IBS-C. We recommend that IBS-A be defined as at least one change between IBS-D and IBS-C by Rome II criteria over a 1-year period.
    Gastroenterology 03/2005; 128(3):580-9. · 12.82 Impact Factor
  • Alisha Ali PhD, Brenda B. Toner PhD
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    ABSTRACT: This study investigated emotional abuse in two samples of women: an immigrant sample of Caribbean-Canadian women, and a sample of women living in the Caribbean. Using a semi-structured interview methodology, it was found that the two samples did not differ in the percentage of participants reporting emotional abuse. However, the following two differences did emerge: (1) the Caribbean-Canadian women reported more emotional abuse in the workplace while the Caribbean women reported more emotional abuse in intimate relationships; and (2) the Caribbean-Canadian women were more likely to cite the cause of their emotional abuse as being systemic in nature while the Caribbean women were more likely to cite an individual as the cause of their abuse. These differences demonstrate the importance of considering cross-cultural influences on the experience of emotional abuse.
    Journal of Emotional Abuse 01/2005; 5(1):125-140.
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    ABSTRACT: Patients with irritable bowel syndrome (IBS) have reduced pain thresholds for rectal distension. In addition, the prevalence of sexual/physical abuse in referred IBS patients is high and is associated with greater pain reporting, poorer health status, and poorer outcome. This lead to a hypothesis that abuse history may sensitise patients to report pain at a lower threshold. To compare rectal pain thresholds in women with IBS who had a history of severe abuse to IBS women with no history of abuse. We studied 74 IBS patients with a history of severe physical and/or sexual abuse and 85 patients with no history of abuse. Abuse history was assessed by a previously validated self-report abuse screening questionnaire. Rectal sensory thresholds were assessed using an electronic barostat and determined by the ascending method of limit (AML) and by the tracking technique. IBS patients with a history of severe abuse had significantly higher rectal pain thresholds, as measured by AML (F (1, 111) = 6.06; p = 0.015) and the tracking technique (F (1, 109) = 5.21; p = 0.024). Patients with a history of severe abuse also reported a significantly higher threshold for urgency to defecate (F (1, 113) = 11.23; p =.001). Severe sexual/physical abuse is associated with higher urge and pain thresholds for rectal distension in IBS patients. This suggests that the greater pain reporting and poorer health status in IBS patients with abuse history are not related to increased rectal pain sensitivity. Further studies are needed to determine the causes of these findings.
    Gut 07/2004; 53(6):838-42. · 10.73 Impact Factor
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    ABSTRACT: Impaired quality of life and psychological distress are common in irritable bowel syndrome (IBS) and may be associated with unhelpful cognitions. Hypnotherapy (HT) is effective in improving both symptoms and quality of life in patients with IBS, and this study was designed to determine whether this improvement is reflected in cognitive change using a validated scale recently developed for use in such patients. A total of 78 IBS patients completed a validated symptom-scoring questionnaire, the Hospital Anxiety and Depression (HAD) Scale and the Cognitive Scale for Functional Bowel Disorders (FBDs), before and after 12 sessions of gut-focused HT. HT resulted in improvement of symptoms, quality of life and scores for anxiety and depression (all P's<.001). IBS-related cognitions also improved, with reduction in the total cognitive score (TCS; P<.001) and all component themes related to bowel function (all P<.001). Cognitions were related to symptom severity because the most abnormal cognitive scores were observed in patients with the highest symptom scores (P<.001). Furthermore, a reduction in symptom score following treatment correlated with an improvement in the cognitive score (P<.001). Regression analysis confirmed that the cognitive score had independence from the other scores and did not serve solely as a proxy for symptom improvement. This study shows that symptom improvement in IBS with HT is associated with cognitive change. It also represents an initial step in unravelling the many possible mechanisms by which treatments such as HT might bring about improvement.
    Journal of Psychosomatic Research 03/2004; 56(3):271-8. · 3.27 Impact Factor
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    ABSTRACT: Studies of antidepressants and psychological treatments in functional bowel disorders (FBD) are methodologically limited. The aim of this study was to assess the clinical efficacy and safety of cognitive-behavioral therapy (CBT) against education (EDU) and desipramine (DES) against placebo (PLA) in female patients with moderate to severe FBD (irritable bowel syndrome, functional abdominal pain, painful constipation, and unspecified FBD). We also evaluated the amenability of clinically meaningful subgroups to these treatments. This randomized, comparator-controlled, multicenter trial enrolled 431 adults from the University of North Carolina and the University of Toronto with moderate to severe symptoms of FBD. Participants received psychological (CBT vs. EDU) or antidepressant (DES vs. PLA) treatment for 12 weeks. Clinical, physiologic, and psychosocial assessments were performed before and at the end of treatment. The intention-to-treat analysis showed CBT as significantly more effective than EDU (P = 0.0001; responder rate, 70% CBT vs. 37% EDU; number needed to treat [NNT ], 3.1). DES did not show significant benefit over PLA in the intention-to-treat analysis (P = 0.16; responder rate, 60% DES vs. 47% PLA; NNT, 8.1) but did show a statistically significant benefit in the per-protocol analysis (P = 0.01; responder rate, 73% DES vs. 49% PLA; NNT, 5.2), especially when participants with nondetectable blood levels of DES were excluded (P = 0.002). Improvement was best gauged by satisfaction with treatment. Subgroup analyses showed that DES was beneficial over PLA for moderate more than severe symptoms, abuse history, no depression, and diarrhea-predominant symptoms; CBT was beneficial over EDU for all subgroups except for depression. For female patients with moderate to severe FBD, CBT is effective and DES may be effective when taken adequately. Certain clinical subgroups are more or less amenable to these treatments.
    Gastroenterology 08/2003; 125(1):19-31. · 12.82 Impact Factor
  • Erin Ross, Alisha Ali, Brenda Toner
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    ABSTRACT: This study gathered data from adolescent girls in four regions (Ottawa, North Bay, Toronto, Windsor) concerning key issues in the prevention of depression in young women. Using a participatory methodology, a team of young women worked with researchers to design and conduct focus groups with 48 adolescent girls across Ontario. Major themes emerging from the focus group data fell into five categories: (a) symptoms, (b) contributing factors, (c) alleviating depression, (d) prevention, and (e) barriers to receiving help. These findings should be considered when designing programs targeting depression in young women in order to maximize the accessibility and effectiveness of such initiatives.
    Canadian journal of community mental health = Revue canadienne de santé mentale communautaire 02/2003; 22(1):55-68.
  • Gastroenterology 01/2003; 124(4). · 12.82 Impact Factor

Publication Stats

2k Citations
380.30 Total Impact Points

Institutions

  • 2003–2010
    • University of North Carolina at Chapel Hill
      • • Division of Gastroenterology and Hepatology
      • • Center for Functional GI and Motility Disorders
      Chapel Hill, NC, United States
  • 1987–2010
    • University of Toronto
      • Department of Psychiatry
      Toronto, Ontario, Canada
  • 2002–2008
    • SickKids
      Toronto, Ontario, Canada
  • 2000–2007
    • Centre for Addiction and Mental Health
      Toronto, Ontario, Canada