William Gardner | University of Ottawa | Université d'Ottawa (original) (raw)
Papers by William Gardner
CMAJ Open, 2022
Background: Cannabis-related emergency department visits can be an entry point for youths to ment... more Background: Cannabis-related emergency department visits can be an entry point for youths to mental health and substance use care systems. We aimed to examine trends in cannabis-related emergency department visits as a function of youths' age and sex. Methods: Using administrative data, we examined all visits to emergency departments in Ontario, Canada, from 2003 to 2017, by youth aged 10-24 years (grouped as 10-13, 14-18 and 19-24 yr) to determine trends in cannabis-related emergency department visits. Cannabis-related visits were identified using International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes for cannabis poisoning and mental disorders due to cannabinoids. We categorized presentations as "less severe" versus "more severe" using scores assigned by nurses at triage. Results: We examined 14 697 778 emergency department visits. Cannabis-related visits increased from 3.8 per 10 000 youths (95% confidence interval [CI] 3.5-4.0) in 2003 to 17.9 (95% CI 17.4-18.4) in 2017, a 4.8-fold increase (95% CI 4.4-5.1). Rates increased for both sexes and each age group. Males were more likely to have a visit than females (rate ratios ≥ 1.5 in 2003 and 2017). The number of cannabis-related visits in 2017 was 25.0 per 10 000 (95% CI 24.0-25.9) among youth aged 19-24 years, 21.9 per 10 000 (95% CI 20.9-22.9) among those aged 14-18 years, and 0.8 per 10 000 (95% CI 0.5-1.0) among those aged 10-13 years. In 2017, 88.2% (95% CI 87.3%-89.0%) of cannabis-related visits and 58.1% (95% CI 58.0%-58.2%) of non-cannabis-related visits were triaged as "more severe," (rate ratio 1.52, 95% CI 1.50-1.53). Similarly, in 2017, 19.0% (95% CI 18.0%-20.1%) of cannabis-related visits and 5.8% (95% CI 5.7%-5.8%) of non-cannabis-related visits resulted in hospital admission (rate ratio 3.3, 95% CI 3.1-3.5). Interpretation: Rates of cannabis-related emergency department visit by youths aged 10-24 years increased almost fivefold from 2003 to 2017, with increases in visit severity and hospital admissions. These trends describe an emerging public health problem, and research is needed to identify the causes of this increase and the health and social consequences of cannabis-related visits for these youths.
Curr Directions Psychol Sci, 1993
Journal of Social Issues, 1996
Medical Care, Sep 1, 2002
Efficient and accurate instruments for assessing child psychopathology are increasingly important... more Efficient and accurate instruments for assessing child psychopathology are increasingly important in clinical practice and research. For example, screening in primary care settings can identify children and adolescents with disorders that may otherwise go undetected. However, primary care offices are notorious for the brevity of visits and screening must not burden patients or staff with long questionnaires. One solution is to shorten assessment instruments, but dropping questions typically makes an instrument less accurate. An alternative is adaptive testing, in which a computer selects the items to be asked of a patient based on the patient's previous responses. This research used a simulation to test a child mental health screen based on this technology. Using half of a large sample of data, a computerized version was developed of the Pediatric Symptom Checklist (PSC), a parental-report psychosocial problem screen. With the unused data, a simulation was conducted to determine whether the Adaptive PSC can reproduce the results of the full PSC with greater efficiency. PSCs were completed by parents on 21,150 children seen in a national sample of primary care practices. Four latent psychosocial problem dimensions were identified through factor analysis: internalizing problems, externalizing problems, attention problems, and school problems. A simulated adaptive test measuring these traits asked an average of 11.6 questions per patient, and asked five or fewer questions for 49% of the sample. There was high agreement between the adaptive test and the full (35-item) PSC: only 1.3% of screening decisions were discordant (kappa = 0.93). This agreement was higher than that obtained using a comparable length (12-item) short-form PSC (3.2% of decisions discordant; kappa = 0.84). Multidimensional adaptive testing may be an accurate and efficient technology for screening for mental health problems in primary care settings.
Psychiatric Annals, 2003
... is met."7 He notes that this may explain why contemporary philosophers believe that grat... more ... is met."7 He notes that this may explain why contemporary philosophers believe that gratitude plays a rela-tively small role in ... to be means for advancing the interests of both parties and hence not to be cases of benefits granted in order to help another, and gratitude would be ...
Physician Committee Member: I just try and make sure that there's some scientific basis behind wh... more Physician Committee Member: I just try and make sure that there's some scientific basis behind what they're proposing to do….. and then I try and make sure the safety parameter that they're proposing they follow, are appropriate and adequate, and then I usually summarize my comments so it's that it's generally my opinion, and I then hope that someone, the secondary reviewer, or other people who have potentially more expertise in the given area if I don't, would have more opinions as well. Lay Member: "I think generally the idea is to get the people that really should not be primary reviewers, to be the secondary reviewer. You want lay people, or the, ... you know, the pharmacists, or the lawyers, or nurses ... to be the secondary reviewers." Attorney, Committee Member: "I'm neither a statistician nor a physician, or a nurse or anybody who would be able to make reasonable sense out of the medical side of things. So I figure my main goal there as a lay person is to look at what the hell they're doing and see whether the consent form… fairly decides what's going on and most particularly fairly decides whatever risks they're asking you to undergo." Study Questions a. What issues about applications are the focus of IRB attention; e.g., the scientific validity of a protocol, or issues of risk or informed consent? b. How, if at all, do the occupants of different roles (chair, community member, attorney, scientific expert, etc.) differ in their assessments and discussions of applications? c. How do IRB members identify problems in applications? What information resources do they use and how do they use them? d. How do IRBs organize the work of application review through the use of staff, pre-meeting review and formal meetings? Reviewer: I read the consent form and I sort of have like a little um, game that I play. I imagine that its my mother who's being presented with this consent form, could she understand it? Um, you know would I feel like she knew what she was getting into, would I feel like she had a good sense of what her risks were, um, you know somebody who's not necessarily educated like us. Interviewer: When …[if] the medicine that they're using is kind of advanced do you ever end up using outside sources or...look things up on the internet or ...books or call the PI? Do you do any of that? Reviewer: Yeah, I do use the internet a fair amount to figure out what the drugs are and what they do. If I don't understand it,….sometimes I've contacted [the Chair] occasionally with questions and I've contacted PI's occasionally….but you know [I] rely on the...oncologist here to…. be able to answer them. Reviewer: I think that the science needs to be looked at because, as I'm sure some people have said, if the science isn't valid then any subject who's in that study is needlessly put at risk because no knowledge will be gained from it…I alone, with probably the other physicians, kind of do it, depending on where the protocol comes from. So if its an NIH protocol, we do pretty much say yeah, a lot of really good minds have already looked at this. It's been approved. It would not have gotten funding if it hasn't already meant really stringent criteria. Data Collection u Transcripts of audio recordings of a single meeting of each of 20 IRB panels. u Interviews with: 1. Panel Chairs 2. Protocol reviewers 3. IRB administrators 4. IRB staff
[T]he carefully controlled clinical trials currently conducted premarket under the existing statu... more [T]he carefully controlled clinical trials currently conducted premarket under the existing statutory framework consists of study populations that are commonly different in composition and health status from populations that will use the marketed drug. Study populations are chosen for a legitimate reason: to make data from the trials clearer and thus to make safety and efficacy testing more efficient. After approval, drugs are used by larger and more heterogeneous populations . . . "The Future of Drug Safety: Promoting and Protecting the Health of the Public", IOM Report, 2007, pp. 153.
Psychiat Res, 2010
Impaired recognition of facial affect has been reported in youths and adults with antisocial beha... more Impaired recognition of facial affect has been reported in youths and adults with antisocial behavior. However, few of these studies have examined subjects with the psychiatric disorders associated with antisocial behavior, and there are virtually no data on females. Our goal was to determine if facial affect recognition was impaired in adolescent girls with conduct disorder (CD). Performance on the Ekman Pictures of Facial Affect (POFA) task was compared in 35 girls with CD (mean age of 17.9 years ± 0.95; 38.9% African-American) and 30 girls who had no lifetime history of psychiatric disorder (mean age of 17.6 years ± 0.77; 30% African-American). Forty-five slides representing the six emotions in the POFA were presented one at a time; stimulus duration was 5 s. Multivariate analyses indicated that CD vs. control status was not significantly associated with the total number of correct answers nor the number of correct answers for any specific emotion. Effect sizes were all considered small. Within-CD analyses did not demonstrate a significant effect for aggressive antisocial behavior on facial affect recognition. Our findings suggest that girls with CD are not impaired in facial affect recognition. However, we did find that girls with a history of trauma/neglect made a greater number of errors in recognizing fearful faces. Explanations for these findings are discussed and implications for future research presented.
Irb Ethics and Human Research, 2012
![Research paper thumbnail of Erratum to “Recognition of facial affect in girls with conduct disorder” [Psychiatry Research 175(3) (2010) 246–251]](https://attachments.academia-assets.com/51000385/thumbnails/1.jpg)
](Psychiatry Research, 2010
The Journal of family practice, 2001
The Family APGAR has been widely used to study the relationship of family function and health pro... more The Family APGAR has been widely used to study the relationship of family function and health problems in family practice offices. Data were collected from 401 pediatricians and family physicians from the Pediatric Research in Office Settings network and the Ambulatory Sentinel Practice Network. The physicians enrolled 22,059 consecutive office visits by children aged 4 to 15 years. Parents completed a survey that included the Family APGAR and the Pediatric Symptom Checklist. Clinicians completed a survey that described child psychosocial problems, treatments initiated or continued, and specialty care referrals. Family dysfunction on the index visit often differed from dysfunction at follow-up (kappa=0.24). Only 31% of the families with positive Family APGAR scores at baseline were positive at follow-up, and only 43% of those with positive scores at follow-up had a positive score at the initial visit. There were many disagreements between the Family APGAR and the clinician. The Fami...
Psychiatric Annals, 2001
... is met."7 He notes that this may explain why contemporary philosophers believe that grat... more ... is met."7 He notes that this may explain why contemporary philosophers believe that gratitude plays a rela-tively small role in ... to be means for advancing the interests of both parties and hence not to be cases of benefits granted in order to help another, and gratitude would be ...
Statistics in Medicine, 2008
For the results of randomized controlled clinical trials (RCTs) and related meta-analyses to be u... more For the results of randomized controlled clinical trials (RCTs) and related meta-analyses to be useful in practice, they must be relevant to a definable group of patients in a particular clinical setting. To the extent this is so, we say that the trial is generalizable or externally valid. Although concern about the generalizability of the results of RCTs is often discussed, there are few examples of methods for assessing the generalizability of clinical trial data. In this paper, we describe and illustrate an approach for making what we call generalizability judgments and illustrate the approach in the context of a case study of the risk of suicidality among pediatric antidepressant users.
Psychiatry Research, 2010
a b s t r a c t Impaired recognition of facial affect has been reported in youths and adults with... more a b s t r a c t Impaired recognition of facial affect has been reported in youths and adults with antisocial behavior. However, few of these studies have examined subjects with the psychiatric disorders associated with antisocial behavior, and there are virtually no data on females. Our goal was to determine if facial affect recognition was impaired in adolescent girls with conduct disorder (CD). Performance on the Ekman Pictures of Facial Affect (POFA) task was compared in 35 girls with CD (mean age of 17.9 years ± 0.95; 38.9% African-American) and 30 girls who had no lifetime history of psychiatric disorder (mean age of 17.6 years ± 0.77; 30% African-American). Forty-five slides representing the six emotions in the POFA were presented one at a time; stimulus duration was 5 s. Multivariate analyses indicated that CD vs. control status was not significantly associated with the total number of correct answers nor the number of correct answers for any specific emotion. Effect sizes were all considered small. Within-CD analyses did not demonstrate a significant effect for aggressive antisocial behavior on facial affect recognition. Our findings suggest that girls with CD are not impaired in facial affect recognition. However, we did find that girls with a history of trauma/neglect made a greater number of errors in recognizing fearful faces. Explanations for these findings are discussed and implications for future research presented.
CMAJ Open, 2022
Background: Cannabis-related emergency department visits can be an entry point for youths to ment... more Background: Cannabis-related emergency department visits can be an entry point for youths to mental health and substance use care systems. We aimed to examine trends in cannabis-related emergency department visits as a function of youths' age and sex. Methods: Using administrative data, we examined all visits to emergency departments in Ontario, Canada, from 2003 to 2017, by youth aged 10-24 years (grouped as 10-13, 14-18 and 19-24 yr) to determine trends in cannabis-related emergency department visits. Cannabis-related visits were identified using International Statistical Classification of Diseases and Related Health Problems, 10th Revision codes for cannabis poisoning and mental disorders due to cannabinoids. We categorized presentations as "less severe" versus "more severe" using scores assigned by nurses at triage. Results: We examined 14 697 778 emergency department visits. Cannabis-related visits increased from 3.8 per 10 000 youths (95% confidence interval [CI] 3.5-4.0) in 2003 to 17.9 (95% CI 17.4-18.4) in 2017, a 4.8-fold increase (95% CI 4.4-5.1). Rates increased for both sexes and each age group. Males were more likely to have a visit than females (rate ratios ≥ 1.5 in 2003 and 2017). The number of cannabis-related visits in 2017 was 25.0 per 10 000 (95% CI 24.0-25.9) among youth aged 19-24 years, 21.9 per 10 000 (95% CI 20.9-22.9) among those aged 14-18 years, and 0.8 per 10 000 (95% CI 0.5-1.0) among those aged 10-13 years. In 2017, 88.2% (95% CI 87.3%-89.0%) of cannabis-related visits and 58.1% (95% CI 58.0%-58.2%) of non-cannabis-related visits were triaged as "more severe," (rate ratio 1.52, 95% CI 1.50-1.53). Similarly, in 2017, 19.0% (95% CI 18.0%-20.1%) of cannabis-related visits and 5.8% (95% CI 5.7%-5.8%) of non-cannabis-related visits resulted in hospital admission (rate ratio 3.3, 95% CI 3.1-3.5). Interpretation: Rates of cannabis-related emergency department visit by youths aged 10-24 years increased almost fivefold from 2003 to 2017, with increases in visit severity and hospital admissions. These trends describe an emerging public health problem, and research is needed to identify the causes of this increase and the health and social consequences of cannabis-related visits for these youths.
Curr Directions Psychol Sci, 1993
Journal of Social Issues, 1996
Medical Care, Sep 1, 2002
Efficient and accurate instruments for assessing child psychopathology are increasingly important... more Efficient and accurate instruments for assessing child psychopathology are increasingly important in clinical practice and research. For example, screening in primary care settings can identify children and adolescents with disorders that may otherwise go undetected. However, primary care offices are notorious for the brevity of visits and screening must not burden patients or staff with long questionnaires. One solution is to shorten assessment instruments, but dropping questions typically makes an instrument less accurate. An alternative is adaptive testing, in which a computer selects the items to be asked of a patient based on the patient's previous responses. This research used a simulation to test a child mental health screen based on this technology. Using half of a large sample of data, a computerized version was developed of the Pediatric Symptom Checklist (PSC), a parental-report psychosocial problem screen. With the unused data, a simulation was conducted to determine whether the Adaptive PSC can reproduce the results of the full PSC with greater efficiency. PSCs were completed by parents on 21,150 children seen in a national sample of primary care practices. Four latent psychosocial problem dimensions were identified through factor analysis: internalizing problems, externalizing problems, attention problems, and school problems. A simulated adaptive test measuring these traits asked an average of 11.6 questions per patient, and asked five or fewer questions for 49% of the sample. There was high agreement between the adaptive test and the full (35-item) PSC: only 1.3% of screening decisions were discordant (kappa = 0.93). This agreement was higher than that obtained using a comparable length (12-item) short-form PSC (3.2% of decisions discordant; kappa = 0.84). Multidimensional adaptive testing may be an accurate and efficient technology for screening for mental health problems in primary care settings.
Psychiatric Annals, 2003
... is met."7 He notes that this may explain why contemporary philosophers believe that grat... more ... is met."7 He notes that this may explain why contemporary philosophers believe that gratitude plays a rela-tively small role in ... to be means for advancing the interests of both parties and hence not to be cases of benefits granted in order to help another, and gratitude would be ...
Physician Committee Member: I just try and make sure that there's some scientific basis behind wh... more Physician Committee Member: I just try and make sure that there's some scientific basis behind what they're proposing to do….. and then I try and make sure the safety parameter that they're proposing they follow, are appropriate and adequate, and then I usually summarize my comments so it's that it's generally my opinion, and I then hope that someone, the secondary reviewer, or other people who have potentially more expertise in the given area if I don't, would have more opinions as well. Lay Member: "I think generally the idea is to get the people that really should not be primary reviewers, to be the secondary reviewer. You want lay people, or the, ... you know, the pharmacists, or the lawyers, or nurses ... to be the secondary reviewers." Attorney, Committee Member: "I'm neither a statistician nor a physician, or a nurse or anybody who would be able to make reasonable sense out of the medical side of things. So I figure my main goal there as a lay person is to look at what the hell they're doing and see whether the consent form… fairly decides what's going on and most particularly fairly decides whatever risks they're asking you to undergo." Study Questions a. What issues about applications are the focus of IRB attention; e.g., the scientific validity of a protocol, or issues of risk or informed consent? b. How, if at all, do the occupants of different roles (chair, community member, attorney, scientific expert, etc.) differ in their assessments and discussions of applications? c. How do IRB members identify problems in applications? What information resources do they use and how do they use them? d. How do IRBs organize the work of application review through the use of staff, pre-meeting review and formal meetings? Reviewer: I read the consent form and I sort of have like a little um, game that I play. I imagine that its my mother who's being presented with this consent form, could she understand it? Um, you know would I feel like she knew what she was getting into, would I feel like she had a good sense of what her risks were, um, you know somebody who's not necessarily educated like us. Interviewer: When …[if] the medicine that they're using is kind of advanced do you ever end up using outside sources or...look things up on the internet or ...books or call the PI? Do you do any of that? Reviewer: Yeah, I do use the internet a fair amount to figure out what the drugs are and what they do. If I don't understand it,….sometimes I've contacted [the Chair] occasionally with questions and I've contacted PI's occasionally….but you know [I] rely on the...oncologist here to…. be able to answer them. Reviewer: I think that the science needs to be looked at because, as I'm sure some people have said, if the science isn't valid then any subject who's in that study is needlessly put at risk because no knowledge will be gained from it…I alone, with probably the other physicians, kind of do it, depending on where the protocol comes from. So if its an NIH protocol, we do pretty much say yeah, a lot of really good minds have already looked at this. It's been approved. It would not have gotten funding if it hasn't already meant really stringent criteria. Data Collection u Transcripts of audio recordings of a single meeting of each of 20 IRB panels. u Interviews with: 1. Panel Chairs 2. Protocol reviewers 3. IRB administrators 4. IRB staff
[T]he carefully controlled clinical trials currently conducted premarket under the existing statu... more [T]he carefully controlled clinical trials currently conducted premarket under the existing statutory framework consists of study populations that are commonly different in composition and health status from populations that will use the marketed drug. Study populations are chosen for a legitimate reason: to make data from the trials clearer and thus to make safety and efficacy testing more efficient. After approval, drugs are used by larger and more heterogeneous populations . . . "The Future of Drug Safety: Promoting and Protecting the Health of the Public", IOM Report, 2007, pp. 153.
Psychiat Res, 2010
Impaired recognition of facial affect has been reported in youths and adults with antisocial beha... more Impaired recognition of facial affect has been reported in youths and adults with antisocial behavior. However, few of these studies have examined subjects with the psychiatric disorders associated with antisocial behavior, and there are virtually no data on females. Our goal was to determine if facial affect recognition was impaired in adolescent girls with conduct disorder (CD). Performance on the Ekman Pictures of Facial Affect (POFA) task was compared in 35 girls with CD (mean age of 17.9 years ± 0.95; 38.9% African-American) and 30 girls who had no lifetime history of psychiatric disorder (mean age of 17.6 years ± 0.77; 30% African-American). Forty-five slides representing the six emotions in the POFA were presented one at a time; stimulus duration was 5 s. Multivariate analyses indicated that CD vs. control status was not significantly associated with the total number of correct answers nor the number of correct answers for any specific emotion. Effect sizes were all considered small. Within-CD analyses did not demonstrate a significant effect for aggressive antisocial behavior on facial affect recognition. Our findings suggest that girls with CD are not impaired in facial affect recognition. However, we did find that girls with a history of trauma/neglect made a greater number of errors in recognizing fearful faces. Explanations for these findings are discussed and implications for future research presented.
Irb Ethics and Human Research, 2012
Psychiatry Research, 2010
The Journal of family practice, 2001
The Family APGAR has been widely used to study the relationship of family function and health pro... more The Family APGAR has been widely used to study the relationship of family function and health problems in family practice offices. Data were collected from 401 pediatricians and family physicians from the Pediatric Research in Office Settings network and the Ambulatory Sentinel Practice Network. The physicians enrolled 22,059 consecutive office visits by children aged 4 to 15 years. Parents completed a survey that included the Family APGAR and the Pediatric Symptom Checklist. Clinicians completed a survey that described child psychosocial problems, treatments initiated or continued, and specialty care referrals. Family dysfunction on the index visit often differed from dysfunction at follow-up (kappa=0.24). Only 31% of the families with positive Family APGAR scores at baseline were positive at follow-up, and only 43% of those with positive scores at follow-up had a positive score at the initial visit. There were many disagreements between the Family APGAR and the clinician. The Fami...
Psychiatric Annals, 2001
... is met."7 He notes that this may explain why contemporary philosophers believe that grat... more ... is met."7 He notes that this may explain why contemporary philosophers believe that gratitude plays a rela-tively small role in ... to be means for advancing the interests of both parties and hence not to be cases of benefits granted in order to help another, and gratitude would be ...
Statistics in Medicine, 2008
For the results of randomized controlled clinical trials (RCTs) and related meta-analyses to be u... more For the results of randomized controlled clinical trials (RCTs) and related meta-analyses to be useful in practice, they must be relevant to a definable group of patients in a particular clinical setting. To the extent this is so, we say that the trial is generalizable or externally valid. Although concern about the generalizability of the results of RCTs is often discussed, there are few examples of methods for assessing the generalizability of clinical trial data. In this paper, we describe and illustrate an approach for making what we call generalizability judgments and illustrate the approach in the context of a case study of the risk of suicidality among pediatric antidepressant users.
Psychiatry Research, 2010
a b s t r a c t Impaired recognition of facial affect has been reported in youths and adults with... more a b s t r a c t Impaired recognition of facial affect has been reported in youths and adults with antisocial behavior. However, few of these studies have examined subjects with the psychiatric disorders associated with antisocial behavior, and there are virtually no data on females. Our goal was to determine if facial affect recognition was impaired in adolescent girls with conduct disorder (CD). Performance on the Ekman Pictures of Facial Affect (POFA) task was compared in 35 girls with CD (mean age of 17.9 years ± 0.95; 38.9% African-American) and 30 girls who had no lifetime history of psychiatric disorder (mean age of 17.6 years ± 0.77; 30% African-American). Forty-five slides representing the six emotions in the POFA were presented one at a time; stimulus duration was 5 s. Multivariate analyses indicated that CD vs. control status was not significantly associated with the total number of correct answers nor the number of correct answers for any specific emotion. Effect sizes were all considered small. Within-CD analyses did not demonstrate a significant effect for aggressive antisocial behavior on facial affect recognition. Our findings suggest that girls with CD are not impaired in facial affect recognition. However, we did find that girls with a history of trauma/neglect made a greater number of errors in recognizing fearful faces. Explanations for these findings are discussed and implications for future research presented.