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Attention Deficit-Hyperactivity Disorder (ADHD) is present in both DSM-IV and ICD-10, with slight differences. For instance, one item is allocated to hyperactivity in DSM-IV and to impulsivity in ICD-10. ADHD is best conceived as a set of core symptoms with some specificity in phenotypal symptomatology. Regarding the specific components, their number remains an open question, the answer oscillating between two (Attention and Hyperactivity-Impulsivity) and three (Attention, Hyperactivity, and Impulsivity).
The aim of this study is to contrast alternative measurement models of instruments assessing ADHD symptoms (2 versus 3 specific factors, hierarchical versus bifactor models) across instruments, and age groups.
We analysed data from the new ChiP-ARD study. Youths (n = 892) aged 5 to 18 years-old were randomly selected and rated by their teachers (ADHD-Rating Scale, and SWAN). Parents (n = 1,171) of these youths rated their own behaviour using the Adult ADHD Symptom Rating Scale (ASRS). The fit of alternative models for ordered-categorical items was tested using the robust Weighted Least Square Estimator (WLSMV).
Results support a bifactor model including one global ADHD factor and two specific Inattention and Hyperactivity- Impulsivity factors. The results also show that the Hyperactivity-Impulsivity factor is improperly defined, and unreliable, calling into question the existence of this subtype. Furthermore, the fit improved when Impulsivity was measured by 4 (ICD-10) versus 3 (DSM-IV) items.
ADHD is a continuous condition from childhood to adulthood, and the “Talk too much” item is best conceived as a measure of Impulsivity than Hyperactivity.
The attention deficit is the main symptom of the Attention Deficit Hyperactivity Disorder (ADHD) in adults. This diagnosis is difficult in adults and comorbidity with substance abuse (SA) is high. As ADHD influences negatively the prognosis of the patients with SA, it is important to treat the ADHD in individuals with DS. Furthermore, it is common the use of substances to relieve ADHD and its comorbidities's symptoms.
It is known the paradoxical effect of amphetamines in individuals with ADHD and it was also described with cocaine. This characteristic is an important clinical clue to the diagnosis of ADHD and it is a predictor of a positive response to the therapeutics.
It is intended to approach the issues related to the psycopathology, differential diagnosis, prognostic and therapeutic implications when there is comorbidity between ADHD and SA in the adult.
Therapeutic implications of the comorbidity between ADHD and SA.
Materials and methods
Analyses of a clinical case and a non-systematic review of the literature was made.
A 23-year-old woman, lawyer, has the diagnosis of ADHD since childhood. She regularly used cocaine for the last 2 years, without doing any medication, as she felt quiet, relax and focused, being more productive at work. The treatment with prolonged-release methylphenidate allowed to stop the use of cocaine without a recurrence of cognitive symptoms.
The ADHA is an independent risk factor to the SA; The early detection and treatment of ADHD helps to prevent the substance abuse;
Attention Deficit-Hyperactivity Disorder (ADHD) is common in childhood (affecting about 5% of children) and persists into adulthood up to 80% of the time. As a result, up to 3.5% of adults may have ADHD, which much higher rates in parents of children referred for ADHD, as heredity plays a role in ADHD. Thus, screening ADHD in adults is relevant in psychiatric and public health practice. The Adult ADHD Symptom Rating Scale (ASRS) was specifically developed for this reason by the World Health Organisation and translated into many languages, including French.
This study aims to estimate the prevalence rates of ADHD in a community sample of French adults, a population where no valid estimates are currently available.
A total of 1,171 adults were asked to rate their behaviours on the ASRS. The total score on the first six items is used as a screener, and the total score of the full set of 18 items is used for adults scoring in the clinically significant zone on the screener (i.e. two-stage algorithm). Maximum-likelihood prevalence rates were estimated in the entire sample and in gender (men vs. women) and age (below and above 43 years-old) subgroups.
The 6-item screener score suggests that 11.27% of participants (10.59% for females, 12.16% for males, 10.66% for younger adults, 12.16% for older ones). The two-stage algorithm suggests that 2.99% of participants (2.57%/3.53% for females/males, 2.16%/4.19% for younger/older adults) present clinical levels of ADHD, which is the rate commonly reported in other countries.
The Gender Identity Disorder (GID) is characterized by a strong sense of identity with the opposite gender, by a persistent discomfort with the one's gender and with a feeling of inadequacy to the social role of the biological gender.
The possibility of a higher presence of Borderline Personality Disorder (BPD) in patients with GID has been a subject of research in several studies.
The diagnosis criteria of the BPD includes a global disorder in the individual identity.
Both BPD and GID are associated with a high risk of self-mutilation and suicide.
To analyze and discuss a case report, addressing subjects related to the psychopatology, differential diagnosis and prognosis and therapeutic implications.
Our discussion is focused on a case report, that led us to a non systematic review of the literature.
Our case report is related to a 20 year old man with GID and BPD. This situation is lived in a great social isolation and frequent self-mutilation episodes and suicide attempts.
The clinical outcome is aggravated by a severe instability in the personal relationships, self-image, ambitions and the future projects.
We have discussed the differential diagnosis, psychopatology, prognosis and the identity disorder that the subject presents.
The biologic gender, age and the treatment phase are factors that influence the risk of suicide and self-mutilation in these patients. We did not found a higher probability of BPD in a patient with GID.
In many European countries including France, awareness for Attention Deficit-Hyperactivity Disorder (ADHD) is increasing. Unfortunately, estimates of prevalence based on validated instruments and reasonably large and representative samples are still lacking in many of these countries.
This study aims to estimate the prevalence rates of ADHD in school-aged children based on teacher ratings of the ADHD rating scale (ADHD-RS-IV) and of the Strengths and Weaknesses of ADHD-Symptoms scale of the Normal-Behavior (SWAN). These scales differ in item wording and scoring, and have both been extensively validated.
892 youths aged from 5 to 18 are included in the present study. Maximum-likelihood prevalence rates were estimated (based on recommended scoring criteria) in the entire sample and in gender (boys vs. girls) and age (below and above 12 years-old) subgroups.
Using the ADHD-RS, 10.65% of youths might have ADHD (4.37% Predominantly Inattentive subtype, 3.36% Combined subtype and 2.91% Predominantly Hyperactive-Impulsive subtype). Boys were more affected than girls (sex ratio 1.4:1), children were more affected than adolescents, and ADHD girls were more likely to be of the Inattentive subtype. Using the SWAN, 2.25% of youths might have ADHD (1.13% Combined subtype, .90% Predominantly Hyperactive-Impulsive subtype, .34% Predominantly Inattentive subtype). No overall differences between genders were observed, children were more affected than adolescents, and ADHD boys were more likely to be of hyperactive-impulsive subtype.
There are true differences according to the rating scales. Teacher ratings provide useful information that also has to be combined with parental and clinical ratings.
Background: Cervical sponylotic myelopathy (CSM) may present with neck and arm pain. This study investiagtes the change in neck/arm pain post-operatively in CSM. Methods: This ambispective study llocated 402 patients through the Canadian Spine Outcomes and Research Network. Outcome measures were the visual analogue scales for neck and arm pain (VAS-NP and VAS-AP) and the neck disability index (NDI). The thresholds for minimum clinically important differences (MCIDs) for VAS-NP and VAS-AP were determined to be 2.6 and 4.1. Results: VAS-NP improved from mean of 5.6±2.9 to 3.8±2.7 at 12 months (P<0.001). VAS-AP improved from 5.8±2.9 to 3.5±3.0 at 12 months (P<0.001). The MCIDs for VAS-NP and VAS-AP were also reached at 12 months. Based on the NDI, patients were grouped into those with mild pain/no pain (33%) versus moderate/severe pain (67%). At 3 months, a significantly high proportion of patients with moderate/severe pain (45.8%) demonstrated an improvement into mild/no pain, whereas 27.2% with mild/no pain demonstrated worsening into moderate/severe pain (P <0.001). At 12 months, 17.4% with mild/no pain experienced worsening of their NDI (P<0.001). Conclusions: This study suggests that neck and arm pain responds to surgical decompression in patients with CSM and reaches the MCIDs for VAS-AP and VAS-NP at 12 months.
Introduction: Identification of severe bacterial infections (SBI) among infants presenting to the emergency department (ED) for fever without a source (FWS) remains challenging. Controversies persist on the usefulness of blood biomarkers, especially when used for assessing infants 22 to 60 days old. Although C-reactive protein (CRP) and white blood cells count (leucocytes) are commonly prescribed, this practice relies on poor and conflicting evidence. Our objective was to determine the performance of those two markers at identifying SBI. Methods: This is a sub-analysis of an ongoing retrospective cohort study conducted in an academic pediatric ED in Quebec City, that aims to determine whether a lumbar puncture should routinely be performed in the FWS workup of 22 to 60 days old infants. All consecutive charts of eligible febrile infants were reviewed. Premature infants (<37 weeks), as well as infants with chronic diseases, immunodeficiency, previous antimicrobial therapy, in-dwelling catheters, or septic shock were excluded. Among others, data related to final diagnosis and investigations were gathered. Sensitivity, specificity, positive (PPV) and negative (NPV) predictive values, positive (LR+) and negative (LR-) likelihood ratios were estimated for each blood biomarkers. Results: Out of 1261 charts reviewed, 920 patients were included in this analysis. SBI prevalence was 13.0% (95%CI: 10.9-15.2) among infants of our cohort. The sensitivity, specificity, PPV, NPV, LR+ and LR- of the leucocytes <5000 or≥15000/□L were 43% (95%CI: 34-53%), 80% (95%CI: 77-83%), 25% (95%CI: 21-30%), 90% (95%CI: 88-91%), 2.1 (95%CI: 1.7-2.8), and 0.72 (95%CI: 0.61-0.84), respectively. The sensitivity, specificity, PPV and NPV of CRP >= 25 mg/L were 46% (95%CI: 37-56%), 96% (95%CI: 94-97%), 65% (95%CI: 55-73%), and 91% (95%CI: 89-92%), respectively. ROC curves analysis indicates that a CRP≥25 mg/L offers the best LR+ (10.4; 95%CI: 6.9-15.6) with a corresponding LR- of 0.56 (95%CI: 0.47-0.67). Conclusion: When evaluating febrile infants in the ED, leucocytes appear to have limited added value, while CRP≥25 mg/L significantly increases the pre-test probability of SBI. CRP should be considered for inclusion in the workup of FWS for infants of 22 to 60 days of age.
Introduction: Fever is a common presenting complaint in the emergency department (ED). Febrile infants are at particularly high risk of serious bacterial infection including bacterial meningitis. Unfortunately, recommendations as to when to perform a lumbar puncture in febrile infants older than 21 days remain conflicting. Our study seeks to establish the prevalence of bacterial meningitis in infants 22 to 60 days old and to evaluate the performance of our local fever without a source (FWS) workup protocol at identifying bacterial meningitis. Methods: This analysis represents the results of a retrospective cohort study which took place in an academic pediatric ED in Quebec City. Infants 22 to 60 days old investigated for FWS, were included in the study. Premature infants ( <37 weeks), as well as infants with chronic diseases, immunodeficiency, previous antimicrobial therapy, in-dwelling catheters, or septic shock were excluded. We evaluated the performance of our local FWS workup protocol which includes the Yale Scale, a complete blood count, blood culture, C-reactive protein, urinalysis and urine culture. The protocol recommends a lumbar puncture in all febrile infants <1 month old, and in all infants <3 months old with either leukocytes <5.0 or >15.0 X 10^9cells/L, petechia, or a Yale between 11 and 16. Results: We reviewed 1261 charts from 2012 to 2017, of which 920 met our inclusion criteria. In our cohort, 171 infants were 22 to 30 days old, 369 were 31 to 45 days old, and 380 were 46 to 60 days old. The proportion of infants with cerebrospinal fluid analysis in these 3 groups was 76% (n = 130), 25% (n = 98) and 12% (n = 46) respectively. In the entire cohort, two infants were diagnosed with bacterial meningitis resulting in a prevalence of 0.2% (95%CI: 0-0.5%); viral meningitis had a prevalence of 4.7% (95%CI: 3.3-6.1%). Sensitivity and specificity of the protocol were 100% and 52.8%; positive and negative predictive values were 0.4% and 100%, respectively. All charts were reviewed for 2 weeks following the index visit to screen for missed cases of bacterial meningitis. Conclusion: Systematically performing a lumbar puncture for workup of fever without a source in infants 22 to 60 days old appears unwarranted given the low prevalence of bacterial meningitis in this population. Our FWS workup protocol correctly identified the 2 cases of bacterial meningitis in our cohort. This is an ongoing study and more cases will be recruited to better evaluate the safety and performance of our protocol.
The Sahara was wetter and greener during multiple interglacial periods of the Quaternary, when some have suggested it featured very large (mega) lakes, ranging in surface area from 30,000 to 350,000 km2. In this paper, we review the physical and biological evidence for these large lakes, especially during the African Humid Period (AHP) 11–5 ka. Megalake systems from around the world provide a checklist of diagnostic features, such as multiple well-defined shoreline benches, wave-rounded beach gravels where coarse material is present, landscape smoothing by lacustrine sediment, large-scale deltaic deposits, and in places, tufas encrusting shorelines. Our survey reveals no clear evidence of these features in the Sahara, except in the Chad basin. Hydrologic modeling of the proposed megalakes requires mean annual rainfall ≥1.2 m/yr and a northward displacement of tropical rainfall belts by ≥1000 km. Such a profound displacement is not supported by other paleo-climate proxies and comprehensive climate models, challenging the existence of megalakes in the Sahara. Rather than megalakes, isolated wetlands and small lakes are more consistent with the Sahelo-Sudanian paleoenvironment that prevailed in the Sahara during the AHP. A pale-green and discontinuously wet Sahara is the likelier context for human migrations out of Africa during the late Quaternary.
Introduction: Prevalence and incidence of delirium in older patients admitted to acute and long-term care facilities ranges between 9.6% and 89% but little is known in the context of emergency department (ED) incident delirium. Literature regarding the incidence of delirium in the ED and its potential impacts on hospital length of stay (LOS), functional status and unplanned ED readmissions is scant, its consequences have yet to be clearly identified in order to orient modern acute medical care. Methods: This study is part of the multicenter prospective cohort INDEED study. Three Canadian EDs completed the two years prospective study (March-July 2015 and Feb-May 2016). Patients aged 65 years old, initially free of delirium with an ED stay 8hours were followed up to 24h after ward admission. Patients were assessed 2x/day during their entire ED stay and up to 24 hours on hospital ward by research assistants (RA). The primary outcome of this study was incident delirium in the ED or within 24 h of ward admission. Functional and cognitive status were assessed using validated Older Americans’ Resources and Services and the Telephone Interview for Cognitive Status- modified tools. The Confusion Assessment Method (CAM) was used to detect incident delirium. ED and hospital administrative data were collected. Inter-observer agreement was realized among RA. Results: Incident delirium was not different between sites, nor between phases, nor between times from one site to another. All phases confounded, there is between 7 to 11% of ED related incident delirious episodes. Differences were seen in ED LOS between sites in non-delirious patients, but also between some sites for delirious participants (p<0.05). Only one site had a difference in ED LOS between their delirious and non-delirious patients, respectively of 52.1 and 40.1 hours (p<0.05). There is also a difference between sites in the time between arrival to the ED and the incidence of delirium (p=0.003). Kappa statistics were computed to measure inter-rater reliability of the CAM. Based on an alpha of 5%, 138 patients would allow 80% power for an estimated overall incidence proportion of 15 % with 5% precision.. Other predictive delirium variables, such as cognitive status, environmental factors, functional status, comorbidities, physiological status, and ED and hospital length of stay were similar between sites and phases. Conclusion: The fact that incidence of delirium was the same for all sites, despite the differences of ED LOS and different time periods suggest that many other modifiable and non-modifiable factors along LOS influenced the incidence of ED induced delirium. Emergency physician should concentrate on improving senior-friendly environment for the ED.
Introduction: It is documented that physicians and nurses fail to detect delirium in more than half of cases from various clinical settings, which could have serious consequences for seniors and for our health care system. The present study aimed to describe the rate of documented incident delirium in 5 Canadian Emergency departments (ED) by health professionals (HP). Methods: This study is part of the multicenter prospective cohort INDEED study. Patients aged 65 years old, initially free of delirium with an ED stay 8hours were followed up to 24h after ward admission. Delirium status was assessed twice daily using the Confusion Assessment Method (CAM) by trained research assistants (RA). HP reviewed patient charts to assess detection of delirium. HP had no specific routine detection of delirious ED patients. Inter-observer agreement was realized among RA. Comparison of detection between RA and HP was realized with univariate analyses. Results: Among the 652 included patients, 66 developed a delirium as evaluated with the CAM by the RA. Among those 66 patients, only 10 deliriums (15.2%) were documented in the patients medical file by the HP. 54 (81.8%) patients with a CAM positive for delirium by the RA were not recorded by the HP, 2 had incomplete charts. The delirium index was significantly higher in the HP reported group compared to the HP not reported, respectively 7.1 and 4.5 (p<0.05). Other predictive delirium variables, such as cognitive status, functional status, comorbidities, physiological status, and ED and hospital length of stay were similar between groups. Conclusion: It seems that health professionals missed 81.8% of the potential delirious ED patients in comparison to routine structured screening of delirium. HP could identify patients with a greater severity of symptoms. Our study points out the need to better identify elders at risk to develop delirium and the need for fast and reliable tools to improve the screening of this disorder.
There is a relative consensus about the detrimental impact of childhood maltreatment on later mental health problems and behavioral difficulties. Prior research suggests that neurophysiological stress mechanisms may partly mediate this association. However, inconsistent findings regarding hypothalamic-pituitary-adrenal axis and sympathetic responses to stress complicate this investigation. Furthermore, the concordance in these two stress systems is not well understood. We tested whether the severity of maltreatment affected the association between maltreatment and cortisol and heart rate (HR) stress responses and the symmetry of these responses. Participants were 155 males (56 maltreated and 99 controls) aged 18 to 35 years. Cortisol and HR were measured in response to the Trier Social Stress Test. Childhood maltreatment, sociodemographic factors, and health-related factors were measured using self-reported questionnaires. Maltreated participants had higher cortisol responses to stress in comparison to controls. However, a shift from moderate to lower to higher cortisol responses was noted as the severity of the experiences increased. Participants exposed to more experiences of maltreatment also showed a greater symmetry between cortisol and HR stress responses. Our findings provide further support for persistent dysregulation of the HPA axis following childhood maltreatment, of which the expression and symmetry with the sympathetic system may change according to the severity of experiences.
Identifying climates favoring extreme weather phenomena is a primary aim of paleoclimate and paleohydrological research. Here, we present a well-dated, late Holocene Dead Sea sediment record of debris flows covering 3.3 to 1.9 cal ka BP. Twenty-three graded layers deposited in shallow waters near the western Dead Sea shore were identified by microfacies analysis. These layers represent distal subaquatic deposits of debris flows triggered by torrential rainstorms over the adjacent western Dead Sea escarpment. Modern debris flows on this escarpment are induced by rare rainstorms with intensities exceeding >30 mm h−1 for at least one hour and originate primarily from the Active Red Sea Trough synoptic pattern. The observed late Holocene clustering of such debris flows during a regional drought indicates an increased influence of Active Red Sea Troughs resulting from a shift in synoptic atmospheric circulation patterns. This shift likely decreased the passages of eastern Mediterranean cyclones, leading to drier conditions, but favored rainstorms triggered by the Active Red Sea Trough. This is in accord with present-day meteorological data showing an increased frequency of torrential rainstorms in regions of drier climate. Hence, this study provides conclusive evidence for a shift in synoptic atmospheric circulation patterns during a late Holocene drought.
We assessed clinicians’ continuing professional development (CPD) needs at family practice teaching clinics in the province of Quebec. Our mixed methodology design comprised an environmental scan of training programs at four family medicine departments, an expert panel to determine priority clinical situations for senior care, a supervisors survey to assess their perceived CPD needs, and interviews to help understand the rationale behind their needs. From the environmental scan, the expert panel selected 13 priority situations. Key needs expressed by the 352 survey respondents (36% response rate) included behavioral and psychological symptoms of dementia, polypharmacy, depression, and cognitive disorders. Supervisors explained that these situations were sometimes complex to diagnose and manage because of psychosocial aspects, challenges of communicating with patients and families, and coordination of interprofessional teams. Supervisors also reported more CPD needs in long-term and home care, given the presence of caregivers and complexity of senior care in these settings.
Background: No standardized method of resident operative-case logging exists. Our study sought to develop a standardized form used by residents to log operative-cases. Methods: Members of the Canadian Neurosurgery Research Collaborative (CNRC), a national resident-led research organization have created a standardized document based on the current Royal College objectives for operative procedures (section 5). Modifications to structure and content will be guided via consensus from Canadian neurosurgery program-directors. Results: Program directors in each CNRC collaborative institution will be asked to modify the standardized form. The CNRC currently involves thirteen of the fourteen Canadian neurosurgery residency programs. Additional consensus, if necessary, can be reached at the Royal College meeting for program directors of neurosurgery March 20th 2017. Conclusions: A standardized operative-case log represents the first step in a prospective study towards compiling operative volume of all Canadian neurosurgical residents over one academic year. Such data will be essential to guide informed decisions with regard to Royal College requirements as Canadian neurosurgical programs transition to a competency based framework.
This study investigated the potential environmental effects of peer victimization and the quality of relationships with parents and friends on diurnal cortisol secretion in mid-adolescence.
This study used the monozygotic (MZ) twin-difference design to control for genetic effects and thus estimate the unique environmental influences on diurnal cortisol. Participants were 136 MZ twin pairs (74 female pairs) for whom cortisol was assessed four times per day over four collection days grouped in a 2-week period in grade 8 (mean age = 14.07 years). Participants also provided self-reports of peer victimization from grade 4 to grade 8 and of the relationship quality with the mother, father and best friend in grade 8.
The expected pattern of diurnal cortisol secretion was observed, with high levels at awakening followed by an increase 30 min later and a progressive decrease subsequently. Controlling for a host of confounders, only within-twin pair differences in peer victimization and a problematic relationship with the mother were significantly linked to twin differences in diurnal cortisol secretion. Specifically, whereas a more problematic mother–child relationship was associated with morning cortisol secretion, peer victimization was linked to cortisol secretion later in the day (diurnal slope).
Controlling for genetic influences and other confounders, stressful relationships with peers and the mother exert unique and time-specific environmental influences on the pattern of diurnal cortisol secretion in mid-adolescence.
Among the solar proxies, κ1 Cet, stands out as potentially having a mass very close to solar and a young age. We report magnetic field measurements and planetary habitability consequences around this star, a proxy of the young Sun when life arose on Earth. Magnetic strength was determined from spectropolarimetric observations and we reconstruct the large-scale surface magnetic field to derive the magnetic environment, stellar winds, and particle flux permeating the interplanetary medium around κ1 Cet. Our results show a closer magnetosphere and mass-loss rate 50 times larger than the current solar wind mass-loss rate when Life arose on Earth, resulting in a larger interaction via space weather disturbances between the stellar wind and a hypothetical young-Earth analogue, potentially affecting the habitability. Interaction of the wind from the young Sun with the planetary ancient magnetic field may have affected the young Earth and its life conditions.
This is the first report of Bactra bactrana (Kennel, 1901) (Lepidoptera: Tortricidae) attacking a major solanaceous crop, sweet pepper Capsicum annuum L. The infestation was detected in two greenhouses at the area of Tympaki (Southern Crete, Greece). The moth larvae caused typical symptoms of a fruit borer with numerous small holes on the surface of the peppers and extensive damage on the inside of the fruit as a result of the feeding activity. Unknown factors facilitated this major shift in host range since B. bactrana is typically a stem borer of sedges. In addition, the pest status of B. bactrana is currently under question, as in both cases the infestations by the moth were associated with significant yield losses. B. bactrana was moderately controlled with chemicals registered for Lepidoptera management in sweet pepper due to the boring nature of the infestation. Some comparative taxonomic notes are provided to facilitate accurate pest discrimination of related Bactra species. Finally, biological attributes of the species are summarized and are discussed from pest control and ecological perspectives. Because Bactra species have been used in augmentative releases for the control of sage, the implications of our findings on the release of biocontrol agents are placed in perspective.
Surface rotation rates of young solar-type stars display drastic changes at the end of the pre-main sequence through the early main sequence. This may trigger corresponding changes in the magnetic dynamos operating in these stars, which ought to be observable in their surface magnetic fields. We present here the first results of an observational effort aimed at characterizing the evolution of stellar magnetic fields through this critical phase. We observed stars from open clusters and associations, which range from 20 to 600 Myr, and used Zeeman Doppler Imaging to characterize their complex magnetic fields. We find a clear trend towards weaker magnetic fields for older ages, as well as a tight correlation between magnetic field strength and Rossby number over this age range. Comparing to results for younger T Tauri stars, we observe a very significant change in magnetic strength and geometry, as the radiative core develops during the late pre-main sequence.