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Writing of The Introduction, Rationale and Objectives Dr Tarek Amin Professor of Public Health Cairo University [email protected]
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Page 1: Introduction, rationale and objectives

Writing of The Introduction, Rationale

and Objectives Dr Tarek Amin

Professor of Public HealthCairo University

[email protected]

Page 2: Introduction, rationale and objectives

II-Introduction/background The background/introduction information provides sufficient

content to the reader so they can understand the purpose of the study, the design and the interpretation of the results.

The writer must search for the background information and properly cite all sources used. 

Provides a general overview of the topic of study in the first paragraph to introduce the main idea(s)

Includes clear, focused, accurate and detailed information to understand the science investigated during the study in the middle paragraph(s)

Provides cited support from external resources Previews the study in the last paragraph by summarizing the

purpose and the design.

Page 3: Introduction, rationale and objectives

Local

Global

Focal

Why this topic is important from the global contextWhat is known about in terms of:Burden, morbidity, mortality, costs and preventability

On the country level what is the situation and what attributes are thereFindings of the previous research and their limitations

You approach how will be different, overcoming the previous flawsYour findings will serve in decreasing morbidity, mortality, costs, provide baseline data etc.,

Significance of your researchThe problem statementRationale

Page 4: Introduction, rationale and objectives

Remember not to use “I, our, we” use “The study”, not “My research”!!!!

Page 5: Introduction, rationale and objectives

Significance of your study (rationale)

• It makes the purpose worth pursuing. The significance of the study answers the questions:

Why is your study important?To whom is it important?What benefit(s) will occur if your study is done?

Your study should have a value not only to yourself but also to the community the respondents, has an impact on your field of specialization and you should mention the sectors that will be benefited by your studies.

Guidance in explaining the importance of the study.• The rationale, timeliness, and/or relevance of the study• Possible solutions to existing problems or improvement to

unsatisfactory conditions.• Who are to be benefited and how they are going to be benefited.• Possible implications.

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Rationale

۞ It makes clear how the findings of the proposed study will help

o In resolving uncertainties, o In leading to new scientific

understanding ando In influencing clinical and public health

policy.

Page 7: Introduction, rationale and objectives

Introduction

• The World Health Organization attributes 4.9 million deaths a year to tobacco use, a figure expected to rise to >10 million by year 2030, if the current trend continues [1]. Almost 70% of these premature deaths will be in the developing countries, one third of which will be among children [2], making tobacco use a global epidemic. Despite the fact that the main burden of this epidemic is in the developing countries, most of the related research and management efforts are addressed by, and toward the developed nations [3]. These efforts also tend to focus on the most prevalent methods of tobacco use in these countries, namely cigarettes and smokeless tobacco, and in most instances do not consider those prevalent in developing countries such as WP [4], despite the fact that as many as 100 million people use this method for tobacco smoking [5]. Waterpipe, “Shisha,”“Maassel,”“Hookha,” or “Nargilha” smoking has gained popularity in most countries of the Middle East and is a common practice in the Arabian peninsula, Turkey, India, Pakistan, Bangladesh, and China [6], especially attracting the younger population. Factors that promote WP popularity may include its social acceptance as part of cultural heritage, easy availability, attractive designs, and the availability of flavored aromatic tobacco called “Muassel” [7]. In some Arab countries, WP (Shisha) smoking is considered less of a social stigma than cigarette smoking, and is also associated with less gender differentiation [8–10]. In Syria, among university students, it was found that at least 62.6% of men and 29.8% of women had smoked WP at least once [9]. In Kuwait, a survey among public employees found that 57% of men and 69% of women had used WP at least once [11]. In many European countries and the USA, there has been an upsurge in WP use over the past several years .It is anticipated that this popular form of smoking may become more prevalent due to globalization and immigration to these countries [12]. WP is perceived by many adolescents, the general public, and even some health professionals as being less dangerous than cigarette smoking [7]. The basis for this assumption includes points like—nicotine content of WP is lower than that of cigarettes; water filters out all noxious chemicals, including carbon monoxide, tar, and nicotine; it is less irritating and thus less harmful to the throat and respiratory system; and Muassel “Narghile” tobacco contains fruit, making it a healthy choice [13]. Although individuals of college age seem to be the group most vulnerable to WP use, secondary school students are also susceptible due to the increasing popularity of this form of tobacco [14, 15], which is primarily social in nature. To address the gap in the current literature on prevalence and possible determinants of WP smoking among Saudi adolescents, we specifically hypothesized that males and older adolescents are more likely to smoke WP than females and younger adolescents, respectively. We also predicted that WP smoking among close relatives and friends, and current cigarette smoking increases the likelihood of being a current WP user. Additionally, we predicted that adolescents who believe that WP smoking is a socially acceptable behavior, as a means to socialize, and those having anxiety symptoms are more likely to use WP. The objectives of this study were to define the prevalence, and pattern of WP smoking among secondary school adolescents in Al Hassa, KSA. Second- arily, we aimed to assess their mental health status, health- related knowledge and attitudes toward WP smoking, and to determine the possible psychosocial predictors for adoption of WP smoking.

Page 8: Introduction, rationale and objectives

• Background

Osteoporosis (OP) is a non-communicable global epidemic characterized by deterioration in the micro-architecture of bone tissue that leads to increased bone frailty and suscep- tibility to fragility (low trauma) fractures [1, 2]. With ageing societies and changing disease patterns worldwide, human, social, and economic costs of OP will continue to rise [3]. Osteoporotic fractures accounted for 0.83 % of the world- wide disability caused by non-communicable diseases [2, 4], globally, approximately 200 million women are affected by OP, and in the developed countries one in three women and one in five men over the age of 50 years will sustain an OP-related fracture [4]. Of particular concern are increasing numbers of hip fractures which is estimated to increase to 2.6 and 4.5 million by year2025 and 2050, respectively [5], with expected increase in their accompanying toll in terms of morbidity, mortality, and economic burden in an era of limited health care resources [6, 7]. The burden of OP- related fractures is less well-studied in the developing countries [8]. In the Middle East, information about OP prevalence and OP-related fracture rates is sparse. In Iran, it was estimated that two million people are at risk of OP- related fractures [9]. In Saudi Arabia, Ardawi et al. reported a prevalence of OP among Saudis aged 20 to 79 years to be 44.5 % [10]. Data on fracture rates are also limited in this part of the world. Baddourah et al. found that lifetime risk for all fractures to be 9.3 and 16.7 % in males and females, respectively [11], a figure which is higher than other Asian countries, but less than that found in Europe. Early OP detection is advocated in numerous clinical guidelines, aim- ing at early management and reducing the later impact of this avoidable disease [12, 13]. Many factors hinder early detection of OP with inability to avert OP-related fractures. First, the limited awareness by physicians and the public of the overall fracture burden of OP on society, how to effec- tively predict fracture events and when to initiate therapeutic interventions for prevention of OP-related fractures, is a major contributory factor for the occurrence of OP-related fractures [14]. Secondly, early detection of OP remains largely opportunistic, and its confirmation is dependent on clinician referral for objective assessment of bone health [15], and finally, the absence of effective diagnostic tools to assist physicians especially at primary level in identifying individuals at risk for developing OP and OP-associated fractures [16]. In Saudi Arabia, there is no screening pro- gram for early detection of OP. Furthermore, studies about OP screening and its possible influencing factors at primary level do not exist. This study aimed at estimating the 10- years probability of OP-related fractures and identifies those in need of OP treatment among Saudi adults attending primary care centers (PHCs) in Al Hassa, Saudi Arabia, using FRAX® calculator and also to determine the possible factors that influence OP screening among them.

Page 9: Introduction, rationale and objectives

• Introduction Sickle cell disease (SCD) is a group of inherited red blood cell disorders characterized by the presence of abnormal hemoglobin. The clinical manifestations are diverse and may include vaso-occlusive, hematological and infectious crises [1,2]. SCD is present throughout Saudi Arabia; particularly common in the eastern and southern provinces: Qatif (eastern region) 17.0 %, Gizan (southern region), 10.3%, Ula (Northern region) 8.1 % and Mecca (western region) 2.5 % [3]. Increased life expectancy due to recent medical advances has increased the need to understand more fully the quality of life (QoL) in patients with SCD and factors predicting disease adaptation [4,5]. QoL measures are used not only to assess the psychosocial impact of the disease but also in evaluating the efficacy of medical care [6-9] and it is the goal of health care providers to enhance treatment outcome and restore comfort and well-being of their patients [10]. In particular, health related quality of life (HRQoL) assessments in adolescents with chronic disease condition facilitate doctor–patient communication, they point to areas where patients may experience serious problems, they can be used as diagnostic tools for problem-oriented follow–up care, and the data are strong predictors of survival [11]. Previous research indicated that patients with SCD experienced a lower HRQoL compared to the general adult's population [12] Dampier et al [13] found that children with SCD as well as their parents scored significantly lower on several HRQoL domains including; general physical, motor and independent daily functioning. Trzepacz et al [14] identified deteriorations in social and school competence for children with SCD, compared to healthy peers, but they did not find an association with disease severity as measured by sickle cell genotype. A number of disease-related factors have been found to affect HRQoL in pediatric SCD. Several studies that examined the influence of various determinants including the role of socio- demographics, disease severity and the presence of complications on HRQoL in SCD patients were carried out in the developed countries [12,13,15,16] while in the developing countries similar studies do not exist. Furthermore, adolescent health is a relatively unexplored component of public health in many developing countries [17,18]. Researches on chronic diseases have indicated that HRQoL varies according to socio-demographic characteristics such as income level, educational status, ethnicity, occupational status, age, and gender, with the disadvantaged groups typically reporting lower HRQoL. This association has been reported for many chronic conditions including cancer [19], HIV infection [20], renal disease [21], and sickle cell disease [15]. Also, studies involving healthy populations have indicated that there is an inverse association between children’s HRQoL and family variables such as low parental education, socio-economic status (SES) [22-24] with low family income contributing to caregiver distress in families of children with chronic conditions [25]. Also, Simon et al [26] reported that HRQoL is poorest for children and youth in lower socioeconomic status groups, those with access barriers, adolescents compared with children, and individuals with medical conditions. Studies on the relationship of socio-economic variables and the HRQoL in patients with SCD revealed conflicting results. Van den Tweel et al [27] indicated that children of parents with low educational level perceived a significantly better HRQoL. This phenomenon is difficult to explain, since previous research mainly pointed out that high quality of life scores were related to high parental education, or that education had no effect at all [11,28]. Also, previous research has shown that children with low socioeconomic status (SES) functioned worse than children from middle SES backgrounds [29]. Limitations in HRQoL have been documented consistently for youth with SCD, [15,30,31] particularly as children move into adolescence and young adulthood [32,33]. Sickle cell pain, a common manifestation that is recurrent, acute, and unpredictable, may be the most important disease complication associated with deterioration in physical and psychosocial domains of HRQoL [15,34,35]. Palermo et al [32] reported that sickle cell complications (including pain), in addition to child age and gender, are central to physical but not psychosocial HRQoL in their sample of adolescents with SCD. Yet, Panepinto and colleagues [36] found that only pain, no other SCD complications, was associated with the deterioration in the physical domain of HRQoL but not the psychosocial. Although pain and other sickle cell complications show an association with decrements in engagement in physical activities and in physical domains of HRQoL, documentation of a significant association of pain with psychosocial domains of HRQoL are not consistent [37]. Recently, Brandow et al. [38] examined HRQoL in children with SCD specifically in relation to painful events at presentation to the emergency room and seven days post- discharge. They found that painful events diminished all domains of HRQoL and that these domains improve after the pain resolves. If these variables (socio-demographic and disease related complications) are crucial in determining HRQoL among adolescent patients with SCD, by controlling of these factors, we may better support them with successful transition to adulthood and with less burden on healthcare services [39]. We specifically hypothesized that adolescents with SCD would have decreased mean scores along the different subscales of the HRQoL measure compared to adolescents without SCD. We also predicted that certain demographic factors (increasing age, gender, low socio-economic status) would be related to HRQoL with males and adolescents from lower SES backgrounds reporting lower quality of life. Additionally, we predicted that adolescents with SCD who experienced disease-related complications, frequent pain episodes, and greater health care utilization would report lower quality of life than adolescents with SCD who did not report these factors. The objective of this study were to assess the impairment of the different domains of HRQoL among Saudi adolescents with SCD compared to healthy peers and to define the relationship between socio- demographic variables, the presence of diseases related complications with the degree of impairment in HRQoL.

Page 10: Introduction, rationale and objectives

• Introduction Training in research is an important part of medical education. The attitudes of undergraduate medical

students towards research might be influenced by a number of factors such as previous training and skills in research [1], motivated faculty staff [2] and motivational rewarding environment at the institution [3]. It is essential to inculcate critical thinking and reasoning skills and to develop positive attitudes towards scientific research amongst medical students from the beginning of their carrier [1, 3]. Studies have shown that early involvement in research promotes a tendency to continue the same in later stages of the medical profession [4, 5]. Several studies [1, 4-7] have assessed attitudes towards research and knowledge about scientific research amongst medical students in developed and developing countries. Khan et al., [1] in their cross- sectional study conducted among a group of Pakistani medical students reported moderate level of knowledge towards health research where about 80% of their students were falling in the middle two quartiles of the knowledge score.

Similar trends were demonstrated by the students on the attitude score. Vodopivec et al. [6] who conducted a study with similar questionnaire among first year Croatian medical students found a similar mean knowledge but much lower attitude scores. They have explained their lower scores as to better represent the baseline effect of secondary and high school education on knowledge and attitudes for research of students. Burgoyne et al., [2] found that the majority of Irish medical undergraduate students are motivated to pursue research. Graduate entrants and male students appear to be the most confident regarding their research skills competencies. Furthermore studies that tackled potential barriers for research conduction among under and post graduate medical students are scarce [2, 8, 9] Heavy workload, financial difficulty and poor guidance and support from the medical school were their main barriers mentioned among undergraduate medical students in Ireland [2] while among junior medical faculty a lack of research training was only barrier to have statistically significant difference between those involved in research versus not. This barrier was also reported in a study done earlier in Pakistan. [9, 10] To the best of our knowledge, none of studies that assess the knowledge, attitudes and the perceived barriers towards research among undergraduate medical students have been carried out in any country of Arab gulf region.

The objective of this study was thus to assess the level of knowledge about and attitudes towards and the perceived barriers among medical students to participate in scientific research activities in medical schools at three universities, one each in Saudi Arabia, Bahrain and Kuwait.

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How to determine research priorities? (Importance/Significance)

I- How frequent is the condition relative to other conditions?

PrevalenceAs a cause of death

II- What is the degree of disability or dysfunction due to the condition?

III- Are there cost-effective means to cure, control, or prevent such condition?

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Assignment:

State the rationale (significance) for the proposed study question?

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III-Setting up research objectives.Are the goals you set out to attain in your

research, inform the readers of what you want to achieve .

Extremely important to word them clearly and specifically.

- Main objectives:☼ Should describe the main questions to be addressed by

the research without going into details.☼ Should give a reader a clear idea of the nature of the

research that will be undertaken.

‘ The purpose is to measure the effect of a plasmodium falciparum asexual blood-stage vaccine in reducing morbidity and mortality due to malaria’

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Objectives • Subobjectives: Tackling only one concept

and could be numbered.o Main and subobjectives should formulated

using ACTION words (to assess, to measure, to ascertain, to explore etc., )

o Wording determine your research design o Objectives should be clear, complete, no

place for ambiguity, difficulty in communication or reflecting the research idea.

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Objectives “characteristics”

Clear

Complete

Specific

Identify theMain variables to be correlated

Identify the direction of the

relationship+ + + +

Descriptive studies

Correlation studies (experimental and non experimental)

Hypothesis-testing studies

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Why is asthma among children in Istanbul exceptionally frequent?

The purpose of the study are to determine if the excess asthma in Istanbul is related to a combination of genetic predisposition (estimated by atopy) and socio-economic and/or indoor air pollution.

Page 17: Introduction, rationale and objectives

What are the specific objectives to achieve such type of study?

I. Identify a suitable source of childhood asthma cases and select 200 cases, following a specific case definition.

II. Identify and select suitable control subjects (individuals without asthma).

III. Measure indoor particulate exposure on each of 3 randomly selected days for each participant.

IV. Perform allergy skin test on cases and controls (atopy).

V. Record personal, demographic, and socio-economic information about cases and control.

VI. Compare risk ratio for atopy, low socio-economic status, and increased indoor air pollution between cases and controls.

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• The objectives of this study were to determine prevalence and pattern of LTPA among adult ----, and to define the socio-demographic determinants that correlate with being sufficiently active LTPA.

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• The objectives of this study were to assess the risk behavior and knowledge related to toxoplasmoisis among --- pregnant women attending primary health care centers (PHCs) and to determine socio-demographic characteristics related to risk behavior and knowledge.

Therefore, the aim of our study was to examine the associations of quantitative and qualitative dietary fat intake, serum estrogen level and obesity with the risk of breast cancer in a case-control study among Saudi females including newly diagnosed breast cancer patients.

Page 20: Introduction, rationale and objectives

• Therefore, the aim of our study was to examine the associations of quantitative and qualitative dietary fat intake, serum estrogen level and obesity with the risk of breast cancer in a case-control study among -- females including newly diagnosed breast cancer patients.

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• The objectives of this study were to deter- mine alterations of vitamin D and parathyroid hormone levels and their relationship to insulin resistance among a sample of healthy young adult obese versus their controls and to identify factors that might predict these alterations.

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• The objectives of this study were to assess medical students' knowledge in clinical years at K University, about SPs' and to explore their attitudes toward the current curricular/training in providing them with effective knowledge and necessary skills with regard to SPs.

Page 23: Introduction, rationale and objectives

Concept, variable, indicator Concept Variable

Subjective impressionNo uniformity in understandingCan not be measured as such

Measurable through the degree of precision varies from scale and from variable to variable (attitudes, income, objective)

EffectivenessSatisfactionImpactExcellentHigh achieverSelf esteemRich

GenderAttitudeAgeWeightHeight

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Concept Indicators Variables Decision level

Rich Incomeassets

Income/yearTotal value of homes, boats, cars

1 if > 100,0002 if >2500000

High academic achievement

Average marks/examAverage marks/practicalAggregate marks

% of marks 1 If > 75%2 if > 75%3 if > 80%

Effectiveness of a health program

Number of patientsChanges in morbidityChanges in mortality Changes in nutritional status

No. servicedNo. of illness episode/1000 population.No. of deaths /diseases.Changes in weight

Before-after levels significant changePoint prevalence

Concepts Indicators Variables

Page 25: Introduction, rationale and objectives

Types of variables

Causal model Study design Unit of measurement

Independent InterveningExtraneous Dependent

Active Attribute

Quantitative Qualitative

Continuous Categorical

Constants

Dichotomous

Polytomies

Can be manipulatedChanged or controlled

CharacteristicsAge, gender, genetics

Only one value or category

Page 26: Introduction, rationale and objectives

Smoking

Assumed cause

Independent variable Dependent variable

Assumed effect

Cancer

Affect the relationship

Age of the personExtent of smokingDuration of smokingExercise

Extraneous variablesModulate the cause-effect relationship

Intervening variables Confounders

A confounding variable is associated with the exposure and it affects the outcome, but it is not an intermediate link in the chain of causation between exposure and outcome.

Page 27: Introduction, rationale and objectives

Measurement scalesScale Examples Characteristics

Nominal or classificatory

Tree, water, houseGenderPsychiatric disorders Religions

Each subgroup has a characteristic/property which is common to all classified within that subgroup

Ordinal or ranking

Income Socioeconomic statusEducational statusAttitudes Likert scale

Nominal scale + subgroups have a relationship to one another. Could be ranked in order

Interval TemperatureThrustone scale (attitudinal)

Ordinal+ nominal+ it has a unit of measurement with an arbitrary starting and terminating point.

Ratio Height Income in $Weight AgeAttitudinal score (Guttman scale)

All + it has a fixed stating point (zero).

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Hypotheses and Underlying Principles

Dr. Tarek Tawfik

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Hypothesis definition A hypothesis is written in such a way that it can

be proven or disproved by valid and reliable data-it is in order to obtain these data that we perform our study. Grinnel 1988:200.

Hypothesis has certain characteristics:1. It is a tentative proposition “hunch”2. Its validity is unknown.3. In most cases, it specifies a relationship between

two or more variables.

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Functions of hypothesis

Formulation of a hypothesis provides a study with focus “specific aspects of a research problem to investigate”

What data are necessary to collect to test the hypothesis.

Enables you to specifically conclude what is true or what is false.

Phase I Phase II Phase III

Formulate your Hunch or assumption

Collect the required data

Analyze data To draw conclusionsAbout the hunch-true/false

Process of testing a hypothesis

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Characteristics of a good hypothesis

Simple, Specific, Stated in advance (3Ss)

A-Simple versus complexContains one predictor and one outcome

variable; (a sedentary lifestyle is associated with an increased risk of

proteinuria in patients with diabetes).

A complex hypotheses contains more than one predictor;

(a sedentary lifestyle and alcohol consumption are associated with increased risk of proteinuria in patients with diabetes).

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Simple hypotheses

Or more than one outcome variable; (alcohol consumption is associated with an

increased risk of proteinuria and neuropathy in patients with diabetes).

Complex hypotheses can be readily tested with a single statistical tests and can be easily approached by breaking them into two or more simple hypotheses.

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Simple hypotheses

(smoking cigarettes, cigars, or a pipe is associated with an increased risk of proteinuria in patients with diabetes).

What type of hypotheses is this?

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B-Specific versus Vague

A specific hypothesis leaves no ambiguity about the subjects, the variables, or about how the test of statistical significance will be applied.

it uses concise operational definitions that summarize the nature and source of the subjects and how variables will be measured;

(a history of using tricyclic antidepressant medications, as measured by review of pharmacy records, is more common in patients hospitalized with an admission diagnosis of myocardial infarction at Longview Hospital in the past year than in control hospitalized for pneumonia).

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Specific versus Vague

It is often obvious from the research hypothesis whether the predictor variable and the outcome variable are dichotomous, continuous, or categorical.

(alcohol consumption (in mg/day) is associated with an increased risk of proteinuria (> 30 mg/dL) in patients with diabetes).

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C-In Advance versus After-the-Fact

The hypothesis should be stated in writing at the outset of the study.

A single pre-tested hypothesis creates a stronger basis for interpreting the study results than several hypotheses that emerge as a result of data inspection.

Hypotheses that are formulated after data examination are a form of multiple hypothesis testing that often leads to over-interpreting the importance of the findings.

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Types of hypothesis

Alternate hypothesis

Null hypothesis

Research hypothesis

Hypothesis of no difference

“null hypothesis”

Hypothesisof difference

Hypothesisof point-

prevalence

Hypothesisof association

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Types of hypothesis “examples”

There is no significant difference in the proportion of male and female smokers in the study population. Hypothesis is ?A greater proportion of females than males are smokers in the study population. Hypothesis is ?A total of 60% of females and 30% of males in the study population are smokers. Hypothesis is ?There are twice as many female smokers as male smokers in the study population. Hypothesis is ?

Page 39: Introduction, rationale and objectives

• To address the existing gap in the literature on smoking among adolescents we have tested the following hypotheses: First, older male adolescents are more likely to smoke tobacco than younger and female adolescents. Second, smoking among close relatives (environmental tobacco exposure) and friends (peer pressure) would increase the likelihood (risk) of being current smoker. Finally, certain motives (socializing, imitation, outing, rather than relieve of stress and pleasure) and the presence of depressive and/or anxiety disorders may represent potential predictors for the current smoking status among adolescents.