Biostatistics ii
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The document discusses key concepts in epidemiological measurement including rates, ratios, proportions, sensitivity, specificity, and predictive values. It defines rates as a measure of risk that expresses the number of events over time in a population. Rates can be crude, specific, or standardized. Ratios compare two quantities, while proportions express a part of a whole as a percentage. Sensitivity measures the ability to correctly identify those with a disease, while specificity measures the ability to correctly identify those without disease. Predictive values reflect the diagnostic accuracy of a test based on its sensitivity, specificity, and disease prevalence.
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This document discusses the treatment of psychiatric disorders through pharmacotherapy, psychotherapy, and somatic treatments. It focuses on the role of medications in treating various conditions like mood disorders, schizophrenia, anxiety, sleep disorders, substance use disorders, and others. It provides details on specific drug classes and examples used to treat each condition. It also covers electroconvulsive therapy (ECT) and discusses what it is, how it works, when it may be used, potential side effects, and the ECT administration and recovery process. Psychotherapies are also mentioned as important treatment options.
Qualitative psycho social research
Qualitative psychosocial research aims to understand how people think, feel, and behave in natural settings. It focuses on understanding unique characteristics of individuals and groups and the meanings they attribute to life experiences. This is done through approaches like nomothetic, idiographic, and hermeneutic methods. The research process involves planning studies, collecting data through methods like interviews and observations, analyzing documents and qualitative data, and generating explanations rather than generalizing to populations. The goal is in-depth understanding rather than description.
Mental health issues during global pandemic
This document discusses mental health challenges during the COVID-19 pandemic. It notes that while COVID-19 is highly contagious, it has a relatively low fatality rate. It then identifies groups that are more vulnerable to mental health issues during the pandemic, including healthcare workers, those with pre-existing conditions, and the general population. It lists potential stressors such as lifestyle changes, fear of infection, and lack of treatment. The document recommends increasing physical and emotional reserves, reducing emotional reactions, spreading positive messages, and ensuring adequate rest, diet and activities to cope with mental health challenges during this time.
Ocd ppt
1) Obsessive compulsive disorder (OCD) is an anxiety disorder characterized by recurrent obsessions and compulsions that are time-consuming and cause distress. Common obsessions include thoughts of contamination, doubts, and forbidden or disturbing images. Common compulsions include cleaning, checking, and rituals.
2) OCD has a lifetime prevalence of 2-3% and typically begins in adolescence or early adulthood. It is chronic without treatment and causes impairment in daily functioning. Neuroimaging studies implicate areas like the orbitofrontal cortex, caudate nucleus, anterior cingulate, and thalamus.
3) Treatment involves cognitive behavioral therapy, specifically exposure and response prevention, along with antidepressant
Amisulpride@ use in psychotic illnesses
Amisulpride is an antipsychotic drug introduced in the 1990s to treat psychotic disorders like schizophrenia and bipolar disorder. It works as a partial dopamine agonist at low doses and antagonist at high doses. Studies have found amisulpride to be similarly effective as risperidone and olanzapine for schizophrenia but with less weight gain and metabolic side effects. Network meta-analyses of oral antipsychotics place amisulpride as comparable to other drugs for efficacy but more tolerable in terms of side effects. Amisulpride is recommended for its metabolic benefits when treating negative symptoms, as augmentation for clozapine, and for its low risk of diabetes, dyslipidemia
Online psychotherapy
Online psychotherapy has shown effectiveness that is comparable to in-person psychotherapy. Several studies have found medium effect sizes for online interventions for various psychiatric disorders. While there are challenges like lack of nonverbal cues, benefits include increased accessibility, lower costs, and flexibility. More research is still needed directly comparing online and in-person psychotherapy.
Clock face drawing test
The document discusses the clock face drawing test, which was originally developed in the early 1900s to evaluate soldiers with head injuries. It requires skills such as following directions, language comprehension, visualizing orientation, motor coordination, conceptualization, and number sequencing. Abnormal results on the clock drawing test can indicate issues with fronto-temporo-parietal functioning and constructional apraxia. It is also useful as an early screening test for cognitive impairment and dementia, as sensitivity and specificity rates for detecting dementia range from 36-75% and 72-98%, respectively. There are various scoring systems that can be used to evaluate clock drawings.
Identification of psychiatric disorders in primary care settings
This document provides an overview of psychiatric disorders and their identification in primary care settings. It discusses common psychiatric conditions like mood disorders, schizophrenia, anxiety disorders, and substance use disorders. It outlines factors like biological, psychological, and socio-cultural elements that can contribute to developing a psychiatric disorder. The importance of early diagnosis and treatment in primary care is highlighted. Symptoms of psychiatric disorders that can present in primary care are described. Two case vignettes of patients presenting with obsessive-compulsive disorder and depression are then summarized. Key issues from each case are discussed.
Schizophrenia
Schizophrenia is a severe mental disorder characterized by positive symptoms like delusions and hallucinations, negative symptoms like apathy and anhedonia, as well as cognitive and affective symptoms. It has a prevalence of around 1% globally and typically onset is in young adulthood. Treatment involves pharmacological interventions like antipsychotic medications and biological therapies combined with psychological interventions like cognitive behavioral therapy and social skills training. Prognosis depends on factors like comorbidities, with about a third of people experiencing a good response to treatment.
Approach to a case of personality disorder
Dr. Sujit Kumar Kar discusses the assessment and diagnosis of personality disorders. He notes that personality disorders involve enduring and inflexible patterns of inner experiences and behaviors that deviate from cultural expectations. These patterns manifest in at least two of four domains - cognition, affectivity, interpersonal functioning, and impulse control. Assessment involves collecting information from the individual, family, friends, and other sources to evaluate functioning in these domains. The enduring patterns must cause clinically significant distress or impairment and be stable over time to meet the criteria for a personality disorder diagnosis.
Emerging trends in brain stimulation
The document discusses various newer neuromodulation methods for treating psychiatric disorders such as magnetic seizure therapy, transcranial alternating current stimulation, transcranial random noise stimulation, optogenetics, thermal stimulation, auricular stimulation, trigeminal nerve stimulation, transcranial ultrasound, and chemical stimulation. It provides details on the mechanisms of each method and reviews evidence from human and animal studies. Applications for several of these newer neuromodulation methods in clinical settings like depression, schizophrenia, cognitive enhancement, pain, and epilepsy are also mentioned.
Understanding personality disorders
The document discusses personality disorders and their assessment and management. It defines personality disorders as enduring patterns of inner experiences and behaviors that deviate from cultural expectations. It outlines structural and topographic theories of personality and psycho-sexual development. Factors influencing personality include biological, psychological, and socio-cultural elements. The document describes features of personality disorders including inflexible patterns across life domains that cause distress and impairment. Assessment involves history, clinical interviews, and projective tests. Management can include limited pharmacological interventions for specific symptoms, as well as various psychotherapies.
EEG basics for mental health professionals
EEG basics for Mental Health Professionals provides an overview of EEG (electroencephalography). Some key points covered include:
- Hans Berger invented EEG in 1924 to study how the brain and mind interact with the outside world.
- EEG involves recording the spontaneous electrical activity generated by cortical neurons via electrodes placed on the scalp. These detect extracellular electrical fields from action potentials and synaptic activity.
- The international 10-20 system is commonly used for electrode placement. It allows recording of brain activity from different regions.
- EEG is used to examine background brainwave activity, symmetry between brain hemispheres, abnormal electrical discharges, and artifacts. This can provide information relevant to conditions like epilepsy,
Neuroimaging basics
The document discusses the history and development of CT scans and magnetic resonance imaging (MRI). It notes that Godfrey Hounsfield and Allan McLeod Cormack independently developed the first CT scanner and won the Nobel Prize in 1979 for this work. CT scans use X-rays to create cross-sectional images of the body, and results are measured using Hounsfield units. MRI uses radio waves and strong magnetic fields to form images, and was pioneered by Paul Lauterbur. Both CT and MRI are important medical imaging techniques that can detect various brain abnormalities.
National mental health program
The National Mental Health Programme (NMHP) was introduced in India in 1982 to provide mental healthcare across hospital, rehabilitation, and community settings. It aimed to prevent and treat mental disorders, apply mental health principles to improve overall health, and ensure minimum mental healthcare is available to all. Key factors leading to its development included WHO recommendations and community mental health projects demonstrating the feasibility of integrating services. The District Mental Health Programme (DMHP) was added in 1996 to decentralize services and provide basic mental healthcare in communities to reduce stigma and the burden on hospitals. It has now expanded to over 240 districts across India.
Disaster & mental health
This document discusses the types and impacts of natural and man-made disasters, who they affect, and the roles of first responders. Disasters can be sudden, intense events that disrupt infrastructure and diminish resources for individuals, families, communities and larger regions. They pose both short and long-term health risks, especially for vulnerable groups like children and under-resourced communities. First responders come from various government and non-government organizations who work to prepare for, respond to, and aid in long-term recovery from disasters through services, assessment, referral and rebuilding coordination over time.
Understanding stress
Stress occurs due to events beyond our control like frustrations, other people's behavior, work, health issues, and misunderstandings. The severity of the anxiety and emotional response to stress depends on how severe the stress is and an individual's ability to handle stress. Psychological interventions target stress through rational thinking and being flexible. The response to stress involves changes in neurophysiology and hormones like cortisol. There are three components to the psychological response to stress: an emotional response with physical symptoms, a coping strategy, and defense mechanisms. Coping strategies like problem solving or reducing emotions can be healthy or maladaptive like substance abuse. Defense mechanisms are unconscious responses used in stressful situations like repression, denial, or projection. Stress can lead
Epidemiological studies in psychiatry in India
Epidemiological studies in psychiatry have been conducted in India for over 60 years, starting with Dr. K.C. Dube's 1961 study in Agra. Initial studies found wide variation in prevalence rates of psychiatric disorders from 9.5 to 370 per 1000 population. Landmark international studies provided more standardized approaches. However, Indian studies were inadequate to assess non-psychotic disorders. Substance use epidemiological studies included the National Household Survey and Drug Abuse Monitoring System. The National Mental Health Survey was the largest nationwide survey and found treatment gaps of 73-85% for mental disorders. Ongoing national surveys continue to inform mental healthcare in India.
rTMS in OCD
This document discusses repetitive transcranial magnetic stimulation (rTMS) as a potential treatment for obsessive-compulsive disorder (OCD). It summarizes that rTMS targeting areas of the cortico-striato-thalamo-cortical (CSTC) circuit, which is hyperactive in OCD patients, shows promise in reducing symptoms. Specifically, low-frequency rTMS of the orbitofrontal cortex and supplementary motor area, as well as high-frequency rTMS of the dorsomedial prefrontal cortex may produce response rates of 35-50% according to clinical studies. The document provides guidance on localizing and stimulating the dorsomedial prefrontal cortex as one region that shows reduced connectivity
Depression
Dr. Sujit Kumar Kar discusses depression, including its causes, symptoms, diagnosis and treatment. Some key points include:
- Depression is one of the most common psychiatric illnesses worldwide, affecting people of all ages, races and genders. It causes significant psychological distress and reduces quality of life.
- Symptoms include sadness, loss of interest, low energy, changes in appetite or sleep, feelings of worthlessness, difficulty concentrating and recurrent thoughts of death.
- Depression has biological causes like changes in brain chemistry and genetics, as well as psychosocial factors like stressful life events, substance abuse and medical illnesses.
- Treatment involves medication like antidepressants, psychotherapy, and lifestyle changes. Proper treatment
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Biostatistics ii
- 2. Epidemiological research Need Definition of what is to be measured Clear and precise Valid Acceptable and applicable for large population Establishment of criteria and standards by which it can be measured
- 3. Measurements in epidemiology Mortality Morbidity Disability Presence or absence or distribution of characteristics Demographic variables
- 4. Basic needs of measurement Validity Reliability Accuracy Sensitivity Specificity
- 5. Tools of measurement Disease magnitude is often expressed in terms of Rates Ratios Proportions
- 6. Rate A rate measures the occurrence of some particular event in a population during a given time period It is a statement of the risk of developing a condition It indicates the change in some event in a given population over a period of time
- 7. Rate Expressed as Rate = number of event /population in that time period× 1000 Eg – death rate, birth rate Elements in a “rate” Numerator Denominator Time specification Multiplier
- 8. Rate Types Crude rates (Unstandardized rates) – birth rate , death rate Specific rates – (Due to specific cause or occurring in specific groups or in specific time periods) – MMR, IMR Standardized rates (obtained by direct or indirect method of standardization)- age and sex standardized rated
- 9. Ratios Expresses a relation in size between two random quantities The numerator is not a component of the denominator X: Y = X/Y Eg- doctor-population ratio, male – female ratio
- 10. Proportion A proportion is a ratio which indicates the relation in magnitude of a part of the whole The numerator is always included in the denominator Always expressed in terms of percentage Eg- IQ
- 11. Incidence The number of new cases occurring in a defined population in a specified period of time Incidence = Number of new cases/ population at risk (during the defined period) × 1000
- 12. Prevalence The term disease prevalence refers to all current cases (old and new) existing at a given point of time or over a period of time in a given population Although referred as rate, it is a ratio Two types Point prevalence Period prevalence
- 13. Relation between incidence and prevalence Prevalence = Incidence X Duration Longer is the duration of the disease, greater is the prevalence Disease of acute onset or with rapid recovery or death and short duration is associated with low prevalence
- 14. Evaluation of screening test Screening test result by diagnosis Sensitivity = proportion of positives that are correctly identified by a test = probability of a positive test, given the patient is ill. Specificity = proportion of negatives that are correctly identified by a test = probability of a negative test, given that patient is well. Positive predictive value is the proportion of patients with positive test results who are correctly diagnosed. Negative predictive value is the proportion of patients with negative test results who are correctly diagnosed.
- 15. Evaluation of screening test
- 16. Screening test results Diagnosis Total Diseased Not diseased Positive True positive (a) False positive (b) a+b Negative False negative (c) True negative (d) c+d Total a+ c b+d a+b+c+d Sensitivity = a/(a+c)× 100 Specificity = d/(b+d)× 100 Positive predictive value = a/(a+b)× 100 Negative predictive value = d/(c+d)× 100
- 17. Sensitivity The term was introduced by – Yerushalmy in 1940s as a statistical index of diagnostic accuracy Definition – the ability of a test to identify correctly all those who have a disease (true positive)
- 18. Specificity Definition – the ability of the test to identify correctly those who do not have the disease (true negative)
- 19. An ideal screening test should be 100 percent sensitive and 100 percent specific, this seldom occurs
- 20. Predictive value Performance of a screening test is measured by its “predictive value” It reflects the diagnostic power of the test Predictive accuracy depends upon – Sensitivity Specificity Disease prevalence
- 21. Predictive value Predictive value of a positive test – indicates the probability that a patient with a positive test result has, in fact disease in question More prevalent a disease – more accurate will be the predictive value of a positive screening test Predictive value of a positive result falls as prevalence declines
- 22. Thank You