The clinical application of suicide risk assessment: A theory-driven approach

The interpersonal theory of suicide posits that thwarted belongingness (TB) and perceived burdensomeness (PB) increase suicide ideation; however, studies have found mixed results regarding this hypothesis among psychiatric inpatients. This study aimed to (a) demonstrate how assessing TB and PB using the Interpersonal Needs Questionnaire (INQ) can provide clinically useful information and (b) investigate how statistical methodology may impact the clinical application of the INQ. Participants were 139 (Sample 1) and 104 (Sample 2) psychiatric inpatients. In both samples, ordinal logistic regression results indicated TB and PB, separately, were significant predictors of suicide ideation-related outcomes; however, when examined as simultaneous predictors, TB was no longer a significant predictor. The interaction between TB and PB was not significant for either sample. Despite this, TB and PB scores provided clinically relevant information about suicide ideation-related outcomes. For example, the highest scores on TB and PB indicated a 93% and 95% chance of having some level of distress due to suicide ideation (Sample 1), a 91% and 92% chance of having some level of desire for death, and a 79% and 84% chance of having some level of desire for suicide, respectively (Sample 2). This study also proposes clinical cutoff scores for the INQ (for TB and PB, respectively, cutoff scores were 22 and 17 for distress due to suicide ideation, 33 and 17 for desire for death, and 31 and 22 for desire for suicide). Although these results indicate that multicollinearity between TB and PB may create interpretational ambiguity for clinicians, TB and PB may each be useful separate predictors of suicide ideation-related outcomes in psychiatric inpatient settings and should be incorporated into suicide risk assessment.

KEY PRACTITIONER MESSAGE

The 15-item Interpersonal Needs Questionnaire (an assessment of thwarted belongingness and perceived burdensomeness) should be incorporated into suicide risk assessment. Among psychiatric inpatients, greater thwarted belongingness and perceived burdensomeness, as separate predictors, were associated with increased levels of distress due to suicide ideation, desire for death, and desire for suicide. The highest scores on thwarted belongingness and perceived burdensomeness indicated a 79% to 95% chance of experiencing an elevated level of distress due to suicide ideation, desire for death, or desire for suicide. Recommended clinical cutoff scores were provided. For example, thwarted belongingness cutoff score of 31 and perceived burdensomeness cutoff score of 22 maximized the sensitivity and specificity of the INQ to detect some level of desire for suicide.

Partners or Partners in Crime? The Relationship Between Criminal Associates and Criminogenic Thinking

Meta-analyses examining the risk factors for recidivism have identified the importance of ties with criminal associates as well as thoughts and attitudes conducive to the continuance of criminal behavior (e.g., criminogenic thinking). Criminologists have theorized that a direct relationship exists between the association with criminal peers and the development of criminogenic thinking. The present study empirically explored the relationship between criminal associates and criminogenic thinking in 595 adult male inmates in the United States. It was hypothesized that the proportion of free time spent with and number of criminal associates would be associated with criminogenic thinking, as measured by two self-report instruments, the Measure of Offender Thinking Styles-Revised (MOTS-R) and the Psychological Inventory of Criminal Thinking Styles (PICTS). Hierarchal linear regression analyses demonstrated that the proportion of free time spent with criminal associates statistically predicted criminogenic thinking when controlling for demographic variables. The implications of these findings on correctional practice (including assessment and intervention) as well as future research are discussed.

Therapist Perceptions of Important Therapeutic Factors in Psychotherapy Groups for Male Inmates in State Correctional Facilities

The purpose of this study is to evaluate group therapists’perceptions of therapeutic factors in psychotherapy groups for incarcerated male inmates. Participants (159 group therapy providers from 78 adult male state correctional facilities) completed a survey designed to assess their perceptions about (a) the relative importance of therapeutic factors as group goals, (b) the amount of group time spent discussing and/or processing therapeutic factors, and (c) the level of progress group members made on therapeutic factors. Interpersonal learning, universality, and imparting information appear to be highly valued by group therapists across the three questions mentioned above. Existential factors and corrective recapitulation of the primary family group were consistently rated significantly lower on the three questions of interest as compared to the other therapeutic factors. Implications of these findings and suggestions for further research are highlighted.

Effect of Symptom Information and Intelligence in Dissimulation

This study employed the Basic Personality Inventory (BPI) to differentiate various types of dis-simulation, including malingered psychopathology and faking good, by inmates. In particular, the role of intelligence in utilizing symptom information to successfully malinger was examined. On admission to a correctional facility, 161 inmates completed the BPI under standard instructions and then again under instructions to fake good (n = 55) or to malinger psychotic (n = 35), posttraumatic stress disorder (n = 36), or somatoform (n = 35) psychopathology. Unlike symptom information, intelligence evidenced some support for increasing inmates’ effectiveness in malingering, although there was no relationship between higher intelligence and using symptom information to successfully evade detection. Overall, the BPI was more effective in detecting malingered psychopathology than faking good. Implications for the detection of dissimulation in correctional and forensic settings are discussed.

An MMPI-2 Scale to Detect Malingered Depression (Md Scale)

A specialized Minnesota Multiphasic Personality Inventory–2 (MMPI–2) validity scale was constructed to detect individuals who are knowledgeable about either depression or MMPI-2 detection strategies and who subsequently attempt to malinger depressive symptoms on the MMPI-2. The Malingered Depression (Md) scale consists of 32 items that discriminated college students who feigned depression from those who were genuinely depressed. Further information about the incremental validity and the utility of the Md scale was obtained in a cross-validation study with additional college students who feigned depression and a sample of students with clinically significant depressive symptoms. The results indicate that the Md scale possesses promising value in detecting malingered symptoms of depression.

Envisioning the next generation of behavioral health and criminal justice interventions

The purpose of this paper is to cast a vision for the next generation of behavioral health and criminal justice interventions for persons with serious mental illnesses in the criminal justice system. The limitations of first generation interventions, including their primary focus on mental health treatment connection, are discussed. A person-place framework for understanding the complex factors that contribute to criminal justice involvement for this population is presented. We discuss practice and research recommendations for building more effective interventions to address both criminal justice and mental health outcomes.

Attitudes toward hiring applicants with mental illness and criminal justice involvement: the impact of education and experience

Individuals with mental health diagnoses, as well as those involved in the criminal justice system, experience a number of barriers in the recovery and reintegration progress, including access to stable, prosocial employment opportunities. Employment for these populations is important for establishing financial security, reducing unstructured leisure time, increasing self-worth, and improving interpersonal skills. However, research has demonstrated that individuals with psychiatric and/or criminal backgrounds may experience stigmatizing attitudes from employers that impede their ability to find adequate work. This study aimed to evaluate stigmatizing beliefs toward hypothetical applicants who indicated a mental health history, a criminal history, or both, as well as the effectiveness of psychoeducation in reducing stigma. Participants consisted of 465 individuals recruited from a large university who completed a series of online questions about a given applicant. Results of this study varied somewhat across measures of employability, but were largely consistent with extant research suggesting that mental illness and criminal justice involvement serve as deterrents when making hiring decisions. Overall, psychoeducation appeared to reduce stigma for hiring decisions when the applicant presented with a criminal history. Unfortunately, similar findings were not revealed when applicants presented with a psychiatric or a psychiatric and criminal history. Implications and limitations of these findings are presented, along with suggestions for future research.

Effect of introduction of antibiotic-impregnated shunt catheters on cerebrospinal fluid shunt infection in children: a large single-center retrospective study

OBJECT

Infection after both primary and revision shunt surgeries remains a major problem in pediatric neurosurgical practice. Antibiotic-impregnated shunt (AIS) tubing has been proposed to reduce infection rates. The authors report their experience with AIS catheters in their large pediatric neurosurgery department.

METHODS

The authors conducted a retrospective case review of consecutive shunt operations performed before (1993-2003) and after (2005-2009) introduction of AIS tubing, with analysis of shunt infection rates and causative organisms identified.

RESULTS

The historical control group consisted of 1592 consecutive shunt operations (657 primary insertions), and the AIS study group consisted of 500 consecutive shunt operations (184 primary insertions). Patients ranged in age from 0-17 years. In the historical group, 135 infections were identified (8.4%). In the AIS study group, 25 infections were identified (5%), representing a significant reduction (p < 0.005). The latency to diagnosis of infection was 23 days in the historical group and 139 days in the AIS study group. The infection rates in infants 0-6 months of age were 12.2% (historical group) and 6.7% (AIS group, p < 0.005), and in infants 7-12 months of age the rates were 7.9% (historical group) and 2.7% (AIS group, p < 0.005). In the historical control group, the frequency rank order of causative organisms was coagulase-negative staphylococcus (51.9%), Staphylococcus aureus (31.6%), streptococcus or enterococcus spp. (8.8%), gram-negative organisms (4.4%), and Propionibacterium acnes (2.2%). Organisms responsible for infections in AIS were S. aureus (40%), followed by streptococcus or enterococcus spp. (20%), P. acnes and coagulase-negative staphylococcus (both 16%), and gram-negative organisms (4%). No unusually antibiotic-resistant bacteria were identified in either group. The authors further subdivided the AIS group into those undergoing primary AIS insertion (Subgroup 1), those undergoing revision of non-AIS systems using AIS components (Subgroup 2), and those undergoing revision of AIS systems using AIS components (Subgroup 3). Infection rates were 1.6% in Subgroup 1, 2.5% in Subgroup 2, and 11.7% in Subgroup 3. Staphylococcus aureus was the most common organism identified in infections of the Subgroups 2 and 3.

CONCLUSIONS

Use of AIS tubing significantly improves shunt infection rates in both general pediatric and infant populations with no evidence of increased antibiotic resistance, which is in agreement with previous studies. However, the increased infection rate in revision surgery in children with AIS catheters in situ raises questions about their long-term application.

Systematic review and meta-analysis of hypothermic machine perfusion versus static cold storage of kidney allografts on transplant outcomes

BACKGROUND

Adequate preservation of renal allografts for transplantation is important for maintaining and improving transplant outcomes. There are two prevalent methods: hypothermic machine perfusion and static cold storage. The preferred method of storage, however, remains controversial. The objective was to review systematically the evidence comparing outcomes from these two modalities.

METHODS

A literature search was performed using MEDLINE, Embase, the Cochrane Library, the Transplant Library and the International Clinical Trials Registry Platform. The final date for searches was 30 November 2012. Studies were assessed for methodological quality. Summary effects were calculated as relative risk (RR) with 95 per cent confidence interval (c.i.). Randomized clinical trials (RCTs) and non-RCTs were included, but evaluated separately. Results from RCTs alone were used for meta-analysis.

RESULTS

Eighteen studies met the inclusion criteria, including seven RCTs (1475 kidneys) and 11 non-RCTs (728 kidneys). The overall risk of delayed graft function was lower with hypothermic machine perfusion than static cold storage (RR 0·81, 95 per cent c.i. 0·71 to 0·92; P = 0·002). There was no difference in the rate of primary non-function (RR 1·15, 0·46 to 2·90; P = 0·767). There was a faster initial fall in the level of serum creatinine with hypothermic machine perfusion in two RCTs, but not in another. There was no relationship between rates of acute rejection or patient survival and the method of preservation.

CONCLUSION

Data from the included studies suggest that hypothermic machine perfusion reduces delayed graft function compared with static cold storage. There was no difference in primary non-function, acute rejection, long-term renal function or patient survival. A difference in renal graft survival is uncertain.

Understanding persons with mental illness who are and are not criminal justice involved: a comparison of criminal thinking and psychiatric symptoms

Research has begun to elucidate that persons with mental illness become involved in the criminal justice system as a result of criminality and not merely because of their mental illness. This study aims to clarify the similarities and differences in criminal thinking and psychiatric symptomatology between persons with mental illness who are and are not criminal justice involved. Male and female (n = 94) participants admitted to an acute psychiatric facility completed measures to assess criminal thinking (i.e., Psychological Inventory of Criminal Thinking Styles and Criminal Sentiments Scale-Modified) and psychiatric symptomatology (Millon Clinical Multiaxial Inventory-Third Edition). In addition to the inpatient sample, 94 incarcerated persons with mental illness from a previously conducted study were selected based on their match with the current sample on several key demographic and psychiatric variables. The results of this study indicated that hospitalized persons with mental illness with a history of criminal justice involvement evidenced similar thinking styles to persons with mental illness who were incarcerated. Persons with mental illness without criminal justice involvement evidenced fewer thinking styles supportive of a criminal lifestyle than the incarcerated sample. Furthermore, the persons with mental illness sample with no history of criminal justice involvement showed significantly lower levels of psychopathology shown to be risk factors for criminal justice involvement (e.g., antisocial personality, drug dependence, alcohol dependence). These findings have implications for offender-type classification, development of targeted treatment interventions, and program placement.

Effective prevention of thromboembolic complications in emergency surgery patients using a quality improvement approach

OBJECTIVE

To assess the effectiveness of a multifaceted intervention based on industrial process improvement to identify and sustainably correct deficiencies in thromboprophylaxis delivery.

SUMMARY BACKGROUND DATA

Deep vein thrombosis and pulmonary embolism are major causes of morbidity and mortality in surgical patients, but effective prophylactic treatments are available. Ensuring reliable delivery of the intended thromboprophylaxis is, however, a long-standing problem.

METHODS

Delivery of thromboprophylactic treatment on an emergency general surgery admissions ward was targeted during a multidisciplinary intervention to improve process reliability using industrial quality improvement approaches. Delivery was audited against guidelines before and after 3- month intervention. Clinical outcome was evaluated by reviewing all radiological investigations for suspected Deep Vein Thrombosis (DVT) or Pulmonary Embolism (PE) from patients admitted to the unit in the 1 year immediately before and that immediately after intervention.

RESULTS

Delivery of thromboprophylaxis according to guidelines was improved from 35% before to 87% 3 months after intervention (χ(2)=87.412, p<0.0001) and sustained at 86% 10 months after intervention. Radiologically identified thromboembolic events occurring up to 60 days after admission in patients admitted for over 48 h fell from 23/3075 (0.75%) before to 9/3080 (0.29%) after intervention (HR 0.39, CI 0.29 to 0.53, χ(2)=6.18, p=0.01292). The risk of thromboembolism in the two groups diverged during follow-up to 60 days, before converging again.

CONCLUSIONS

A quality improvement process resulted in major sustainable improvements in the delivery of thromboprophylaxis associated with a 61% reduction in radiologically detected clinical episodes of thromboembolism 2 months after admission. Further study of this approach to improving care quality is warranted.

Vocational Psychology in Corrections

This reaction to the major contribution (MC) “The Vocational Development of Offenders: Barriers, Interventions, and Implications for Social Justice” commends the authors for bringing an understudied and underdiscussed population to counseling psychologists. This reaction provides a contextual response to the MC in its entirety, as well as for the three articles comprising the MC. The authors are commended for educating readers about the complexities of correctional rehabilitation, emphasizing the role of work in the rehabilitation process to reduce criminal recidivism, and examining current vocational practices; however, this reaction provides practical suggestions for improving the integration of best correctional practices into vocational counseling, and provides suggestions for policy change. In addition, this reaction further emphasizes the necessity of counseling psychologists’ involvement in offender rehabilitation.

Surgical correction of tracheo-oesophageal fistula and oesophageal atresia in infants with VACTERL association: a retrospective case-control study

INTRODUCTION

VACTERL is a rare, non-random association comprising at least three major component features defined by the acronym, and including Vertebral anomalies, Anorectal malformations, Cardiac defects, Tracheo-oEsophageal fistula with or without oesophageal atresia (TOF/OA), Renal abnormalities and Limb anomalies. The aim of this study was to compare the post-operative outcomes following surgical correction of TOF/OA in infants with VACTERL and isolated TOF/OA.

METHODS

A retrospective case-control study comparing infants with VACTERL (case group) versus infants with isolated TOF/OA (control group) that underwent surgical correction of TOF/OA at our centre between January 2006 and December 2011. Patient demographics, types of anomalies, operative techniques and post-operative outcomes were collected using inpatient and outpatient records.

RESULTS

We identified 30 consecutive infants with TOF/OA. Five infants had VACTERL (17 %) and 15 infants had isolated TOF/OA (50 %). There was no significant difference in the gestational age (P = 0.79), birth weight (P = 0.69) or operative repair (P = 0.14) between groups. Overall, surgical correction of TOF/OA led to satisfactory morbidity. Infants with VACTERL were not at higher risk of post-operative complications, such as oesophageal stricture (P = 0.17) or gastro-oesophageal reflux (P = 1.0), compared to infants with isolated TOF/OA.

CONCLUSIONS

VACTERL association does not increase the risk of post-operative complications following TOF/OA repair.

The detection of feigning using multiple PAI scale elevations: a new index

Archival data were collected from 98 male inmates at a psychiatric inpatient unit to examine the utility of the Multiscale Feigning Index (MFI) as a proposed feigning index for the Personality Assessment Inventory (PAI). MFI was compared with existing PAI feigning indices, Malingering (MAL), Negative Impression Management (NIM), and Rogers Discriminant Function (RDF), using performance on the Structured Interview of Reported Symptoms (SIRS) as the feigning criterion. Regression analyses revealed that MFI was a stronger predictor of SIRS outcome than NIM, MAL, and RDF. In addition, NIM, MAL, and RDF did not add substantial incremental validity to MFI in predicting SIRS outcome. Receiver operating characteristic analyses revealed sensitivity of 68.89% and specificity of 94.34% at an MFI cutoff of more than 76, which compared favorably with the utility of NIM, MAL, and RDF.

Preservation solutions for static cold storage of kidney allografts: a systematic review and meta-analysis

Static cold storage is the most prevalent method for renal allograft preservation. Several solutions have been designed to counteract the detrimental effects of cold ischemia and reperfusion. The aim of this study was to appraise the evidence for the currently available preservation solutions. We performed a systematic literature search using MEDLINE, EMBASE, the Cochrane Library, the Transplant Library and trial registries. Inclusion criteria specified any comparative, prospective study for deceased donor renal allografts. Studies were assessed for methodological quality. The primary outcome was delayed graft function (DGF). Fifteen trials with a total of 3584 kidneys were included. Eurocollins was associated with a higher risk of DGF than University of Wisconsin solution (UW) in two randomized controlled trials (RCTs) and histidine-tryptophan-ketoglutarate (HTK) in two RCTs. UW was associated with an equal risk of DGF compared with Celsior in three RCTs and HTK in two RCTs. There was limited data regarding other comparisons and outcomes. The choice of preservation solution has an effect on the incidence of DGF, which might, in turn, affect long-term outcomes. Both UW and HTK have lower rates of DGF than Eurocollins. There is no difference in the incidence of DGF with the use of Celsior, HTK and UW. These findings are supported by registry data.

Treating offenders with mental illness: a research synthesis

The purpose of this research synthesis was to examine treatment effects across studies of the service providers to offenders with mental illness. Meta-analytic techniques were applied to 26 empirical studies obtained from a review of 12,154 research documents. Outcomes of interest in this review included measures of both psychiatric and criminal functioning. Although meta-analytic results are based on a small sample of available studies, results suggest interventions with offenders with mental illness effectively reduced symptoms of distress, improving offender's ability to cope with their problems, and resulted in improved behavioral markers including institutional adjustment and behavioral functioning. Furthermore, interventions specifically designed to meet the psychiatric and criminal justice needs of offenders with mental illness have shown to produce significant reductions in psychiatric and criminal recidivism. Finally, this review highlighted admission policies and treatment strategies (e.g., use of homework), which produced the most positive benefits. Results of this research synthesis are directly relevant for service providers in both criminal justice and mental health systems (e.g., psychiatric hospitals) as well as community settings by informing treatment strategies for the first time, which are based on empirical evidence. In addition, the implications of these results to policy makers tasked with the responsibility of designating services for this special needs population are highlighted.

Treating offenders with mental illness: a research synthesis

The purpose of this research synthesis was to examine treatment effects across studies of the service providers to offenders with mental illness. Meta-analytic techniques were applied to 26 empirical studies obtained from a review of 12,154 research documents. Outcomes of interest in this review included measures of both psychiatric and criminal functioning. Although meta-analytic results are based on a small sample of available studies, results suggest interventions with offenders with mental illness effectively reduced symptoms of distress, improving offender's ability to cope with their problems, and resulted in improved behavioral markers including institutional adjustment and behavioral functioning. Furthermore, interventions specifically designed to meet the psychiatric and criminal justice needs of offenders with mental illness have shown to produce significant reductions in psychiatric and criminal recidivism. Finally, this review highlighted admission policies and treatment strategies (e.g., use of homework), which produced the most positive benefits. Results of this research synthesis are directly relevant for service providers in both criminal justice and mental health systems (e.g., psychiatric hospitals) as well as community settings by informing treatment strategies for the first time, which are based on empirical evidence. In addition, the implications of these results to policy makers tasked with the responsibility of designating services for this special needs population are highlighted.

Thinking styles and emotional states of male and female prison inmates by mental disorder status

OBJECTIVES

This study explored criminal thinking styles and feelings of aggression and hopelessness among male and female inmates who reported mental disorders and those who did not.

METHODS

A total of 4,204 respondents (3,986 males and 218 females) who were expected to be released from prison within 24 months completed an hour-long audio computer-assisted self-interview survey that included the Beck Hopelessness Scale, Buss-Perry Aggression Questionnaire Short-Form, and Criminal Sentiments Scale-Modified. Weights were constructed to adjust the sampled population to the full population of the prison.

RESULTS

A mental disorder was reported by 19.8% of male and 46.1% of female participants, with 6.6% of males and 19.4% of females reporting a serious mental disorder. The criminal thinking patterns of male and female inmates who reported mental disorders were consistent with those of inmates who reported no mental disorders; however, levels of criminal attitudes were significantly higher among males reporting serious mental disorders than males reporting other mental disorders or no disorders. Inmates reporting mental disorders scored significantly higher on measures of aggression and hopelessness.

CONCLUSIONS

Results of this study suggest that inmates who report mental disorders have antisocial attitudes consistent with inmates who do not report mental disorders but have levels of aggression and hopelessness that are higher than their counterparts who do not report mental disorders. These findings are vital to the development of evidence-based interventions that respond accurately and holistically to the complex constellation of needs among persons with mental disorders who are involved in the justice system.

A national survey of mental health services available to offenders with mental illness: who is doing what?

The purpose of this study was to examine the national practices of psychotherapy services for male offenders with mental illness (OMI) in state correctional facilities. Participants consisted of 230 correctional mental health service providers from 165 state correctional facilities. Results indicated that mental health professionals provided a variety of services to OMI that can be conceptualized by six goals considered important in their work: mental illness recovery, emotions management, institutional functioning, re-entry, risk-need, and personal growth. Mental health professionals in this study generally viewed mental illness recovery, institutional functioning, and personal growth as significantly more important and spent more time focused on these goals than emotions management, re-entry, and risk-need. Mental health professionals tended to believe the services they provided were effective across four key treatment foci including mental illness, skill development, behavioral functioning, and criminogenic needs with more progress perceived in areas related to mental illness and skill development than their ability to effectively change behavioral functioning. Implications of these findings and directions for future research are discussed.

Inmate attitudes toward treatment: mental health service utilization and treatment effects

This study examined inmate attitudes toward treatment, mental health treatment utilization, and treatment effects that maximize treatment effectiveness. Participants consisted of 278 incarcerated male adult offenders from the Kansas Department of Corrections. Multiple linear regression analysis indicated that inmate attitudes toward treatment were predictive of the number of mental health treatment sessions (dosage) inmates received. Hierarchical linear regression analyses indicated positive help-seeking attitudes were associated with institutional behavior (decreased number and severity of disciplinary infractions) and scores on a measure assessing risk for future criminal behavior; however, the amount of mental health treatment an inmate received (treatment dosage) was associated with problematic institutional behavior (i.e., increased severity and number of disciplinary infractions). These results indicated that treatment dosage and behavioral outcomes were impacted by inmate attitudes toward treatment. As a result, correctional psychologists may be better able to predict which inmates will receive the most benefit from services. Implications of these findings for practitioners and policy makers are discussed.

Prison tattoos as a reflection of the criminal lifestyle

The purpose of this study was to examine the relationship between prison tattoos and the criminal lifestyle and recidivism. Participants consisted of 81 male inmates with prison tattoos (i.e., prison-themed or prison-made tattoos), 75 inmates with nonprison tattoos (e.g., animal tattoos, tattoos of ethnic origin), 52 male inmates with no tattoos, and 66 college students with tattoos. Results indicated that inmates with prison tattoos differed from inmates with nonprison tattoos, inmates without tattoos, and college students with tattoos with regard to criminal thinking styles, were at increased risk of recidivism, and presented more institutional behavioral problems, resulting in more disciplinary infractions. There were no significant differences between inmate groups with regard to number of convictions; however, additional group comparisons indicated that inmates with visible tattoos and antisocial-themed tattoos were at greater risk for recidivism and received more disciplinary infractions than inmates without visible or antisocial-themed tattoos. Implications of these findings are discussed.