A Case-Control Study of Smoking and Alcohol Intake as Prenatal Risk Factors

of Autism Spectrum Disorder (ASD) among Filipino Children

A Research Proposal

Submitted By:

Jimenez, Margaret Stephanie Jimenez, Sarah Jane

Joaquino, John MarquisJordan, Stephanie Patricia

Preceptor:

Dr. Georgina ParedesDepartment of Preventive and Community Medicine

College of Medicine, UERMMMCI

CHAPTER 1.

INTRODUCTION

A. RESEARCH PROBLEMS AND SUBPROBLEMS

Are the following prenatal risk factors, specifically smoking or alcohol intake associated

with Autism Spectrum Disorder among Filipino Children?

B. HYPOTHESIS

Null Hypotheses:

a) There is no difference in the risk of developing autism among children of mothers who

smoke and children of mothers who do not smoke during prenatal period

b) There is no difference in the risk of developing autism among children of mothers who

do drink alcoholic beverages and children of mothers who drink alcoholic beverages

during the prenatal period

Alternative Hypotheses:

a) There is a difference in the risk of developing autism among children of mothers who

smoke and children of mothers who do not smoke during prenatal period

The odds of having a child with ASD is higher among mothers with a higher pack

years of smoking than those with lower pack years

b) There is a difference in the risk of developing autism among children of mothers who do

drink alcoholic beverages and children of mothers who drink alcoholic beverages during

the prenatal period

The odds of having a child with ASD is higher among mothers who are chronic

alcoholic drinkers than those who are not.

c) SIGNIFICANCE OF THE STUDY

ASD is a neurodevelopmental disorder that causes impaired intellectual, communicative

and behavioral development1. As a lifelong debilitating condition, it affects not only the children

with the disease but also their families and caregivers. Thus, it is a disease that has both social

and biological impact, and as such is an urgent public health concern2.

There is a significant population of Filipinos affected by the disease, with an estimated 1

out of every 150 children born with ASD3. Furthermore, autism ranks 3rd out of the top 10

developmental disorders among pediatric patients. However, only 2% of those born with disease

are given appropriate care4. Moreover, the prevalence and risk factors of ASD in the Philippines

are unknown because of lack of funding being given to studies on this disease. The lack of a

national center or institute for diagnostic and treatment procedures underscores the deficiencies

in the identification and care of Filipino children with autism, as well as a lack of a centralized

resource of knowledge about the disease 4.

Finally, since studies agree that interplay between multiple genetic and environmental

factors contribute to the development of ASD 5, findings obtained from studies abroad might not

be applicable to the Filipino population.

Therefore, research on the risk factors of Autism Spectrum Disorders helps to fill a gap in

knowledge about the pathogenesis of the disease, as well as lays the foundation for future

researches in the Philippines.

d) GENERAL AND SPECIFIC OBJECTIVES

General Objective: To determine the association of exposure to prenatal risk factors,

specifically smoking and alcohol intake, in developing Autism Spectrum Disorder

among Filipino children

Specific Objectives:

i. To describe the socio-demographic characteristics of mothers of children (4-

11 years old) with ASD according to:

a) Age of the mothers

b) Age of mothers when they got pregnant

c) Number of children

d) Occupation

e) Income Status

f) Educational Attainment

ii. To determine the prevalence of prenatal smoking and alcohol exposure among

mothers with and without children with ASD

iii. To determine the odds ratio of smoking and drinking alcoholic beverages

before or during pregnancy among mothers of children with ASD versus

mother of children without ASD

iv. To determine which among the socio-demographic maternal characteristics,

prenatal smoking exposure and prenatal alcohol exposure show the strongest

association with the development of ASD among children.

CHAPTER 2.

REVIEW OF RELATED LITERATURE

Autism Spectrum Disorder: An Overview

Autism Spectrum Disorder, or ASD, is a cluster of lifelong behaviorally defined

neurodevelopmental disorders. According to the Diagnostic and Statistical Manual of Mental

Disorders6, it is composed of Autistic Disorder, Asperger’s syndrome, and Pervasive

Developmental Disorder. These are diagnosed through clinical observation, and encompass

impairments in social, communicative, and behavioral development, and are accompanied by

abnormalities in intellectual functioning, learning, attention, and sensory processing. Findings

show that children with ASD present with generalized and profound impairment in executive

functioning, with significant differences compared to typical children with regards to cognitive

flexibility, working memory, and response inhibition7.

Although the studies on the possible genetic causes of ASD are numerous, they agree that

affected individuals are heterogenous in terms of the cause of their disorder as well as the degree

to which each is affected functionally and neurobiologically8. The genetic defect may be in either

a single gene or a combination of genes, each having a small to moderate effect in increasing

ASD risk9. Examples of genetic defects include cell signaling abnormalities, Joubert's syndrome,

Rett's syndrome, tuberous sclerosis, Fragile X syndrome, and maternally inherited duplications

of chromosome 15q11-13. However, these account for only 10% of ASD cases, each single

cause contributing to no more than 1% of cases on average 10.

Thus, the focus of autism research is currently expanding to include the role of

environmental factors in the pathogenesis of the disease5. For example, prenatal factors

significantly associated with ASD are advanced maternal age, parity, and advanced paternal

age11. Although there is insufficient evidence to implicate any one factor in autism etiology,

exposure of a broad class of conditions that compromise perinatal and neonatal health may

increase the risk12. Exposure to smoking and alcohol intake during pregnancy are two common

risk factors for the development of neurodevelopmental disorders, and as such may be associated

with the pathogenesis of ASD13,14.

It must be emphasized that the exact etiology of ASD is not yet known, and studies agree

that an interplay between multiple genetic and environmental factors contribute to the

development of ASD. Thus, findings obtained from studies on ASD abroad might not be

applicable to the Filipino population. This further underscores the need for more research

regarding the disease in the Philippines.

ASD in the Global and Philippine Setting

Surveillance efforts indicated that the age of 8 years old is a reasonable index age at

which monitoring peak prevalence of ADS2. Children who met the criteria of the case definition

for ASD were consistent with records, documented behaviors with the use of the diagnostic and

statistical manual of mental disorders 4th edition, text revision6. To analyze changes in prevalence

of ASD, the CDC compared collected data from 10 sites in the United States and compared data

from the same sites of 20022. 9 sites were observed to have an increase in ASD prevalence with

increases with males in all sites and females in 4 sites out of 10. The study acknowledged that

the proportion of children with characteristics consistent with the criteria for an ASD

classification who had been previously documented ASD classification varied across all sites in

majority of the sites in the United States. Results identified a higher prevalence of ASD for non-

Hispanic white children compared with non-Hispanic black children.

Results also showed showed an increase in prevalence of identified ASD among U.S

children aged 8 and underscore a need to regard ASD as an urgent public health concern 2. In the

United States an average of 1 child in every 150 has ADS and there is needed to improve early

identification of ADS2. There is a lack of awareness about autism among medical professionals1.

Features of children with less than 2 years of age are subtle and difficult to define and the need to

be reassessed of ADS after the age of 2 is required1.

In a descriptive hospital based study with children with autism, the major clinical

symptoms observed and commonest complaints were delayed development of speech and being

lost in one’s own world1. Children presented with difficulties in toilet training. ADS patients

showed no interest in play and used the toys inappropriately. Imaginative and pretend play was

absent. Children expressed behavioral problems like hyperactivity aggression and self-injury,

which is due to increase levels of endorphins1. Continued monitoring is needed to document and

understand changes over time, including the multiple ascertainments and potential risk factors2.

All professionals involved in the diagnosing ASD in children should consider either

LED-10 or DSM-IV-TR systems15. Professionals should aim to identify ASD early since it

provides opportunity for early referral and intervention so the child with ADS may have an

improved functioning later in life. Active monitoring by health care professionals is

recommended of 18 months and again at 24-36 months for key signs of ADS. Every pre-school

child diagnosed with ADS should have an individualized intervention plan that sets out goals,

types, frequency and intensity of intervention15. Continued monitoring is varied according to the

child’s changing need. No single language or communication intervention is appropriate for all

children; the optimal communication intervention for an individual child with ASD depends on

the need of a particular child.

ASD in the Philippines is not well characterized, both in terms of its prevalence and the

management of the disease. According to the Autism Society of the Philippines, the estimated

prevalence of Filipino children with autism in 2007 is 500,0003. However, there is no formal

figure due to the lack of funding towards researches on this disease.

A study by Dr. Alexis Reyes, a leading Filipino Developmental Pediatrician, extrapolated

that 0.5 million Filipinos exhibit neuro-behavioral disorder if the prevalence rate in the United

States will be the basis. Using this figure, only two percent of them will be given appropriate

care16. Data gathered from the Philippine General Hospital reveals that autism is ranked third in

the top 10 developmental disorders16, 17. However, it is important to note that no records from

private hospitals or clinics were obtained.

The study presents significant issues regarding the national outlook on Autism. It

emphasized a strong need for an appropriate national program that addresses the deficiencies

regarding the treatment and care regarding children with autism. Numerous deficiencies with

regards to patient care in the Philippine setting were identified: first, there is a lack of a national

center or institute for diagnostic and treatment procedures. Second, treatment is limited to

Western medical and behavioral approaches which are not always suitable for the cultural needs

of the patients. Third, the role of the non-medical professionals are not recognized. Creative

therapies used by psychologists and counselors are not put in the mainstream and are limited to

private practice. Fourth, the Autism Society of the Philippines, a non-profit organization founded

by parents of children with ASD is not incorporated with the medical professions systemically.

Lastly, the fundamental role of parents and family members with ASD, which is of fundamental

value in the total handling of the disease, is not given recognition.

A more recent local study reported that there is no formal curriculum that addresses the

plight of persons with Autism Spectrum Disorder (ASD) in the educational system17. A few

teachers, on their own, without any formal training in children’s disorders are able to “spot”

possible disorders. These suspected cases are then referred to private practitioners, namely the

Developmental Pediatricians, Psychologists and Psychiatrists. The study also stated that the

number of individuals with ASD is around 570,000 in 1 out of 150 individuals, however this

estimate is again not confirmed. The study suggests that a more comprehensive approach in the

treatment and the handling of ASD patients is needed in the Philippines. It should include non-

medical practitioners and a form of multi-disciplinary team approach to the problem where the

parent should be empowered and have a major role in the team, and that the siblings and

extended family should be tapped as resources especially since Filipinos have close knit family

ties followed by creative therapies per individual.

In summary, the literature shows that in developed countries such as the United States,

Autism Spectrum Disorder is diagnosed and managed systematically, with specific intervention

plans that account for the roles of the parents, the clinicians, and the government. In contrast,

there is no standardized, integrated and comprehensive approach to management of patients with

ASD in the Philippines. Moreover, although the exact prevalence of the disease locally is not

known, it is one of the major developmental disorders among pediatric patients.

Prenatal Alcohol Exposure as a Risk Factor for ASD

Alcohol consumption in moderate amounts is not generally harmful; nonetheless, in

excessive amounts, it can have harmful effects; mainly alcohol dependency or alcoholism

leading to metabolic deficiencies and even injury to major organs particularly the liver and even

the central nervous system. There are however certain situations such as pregnancy whereby

alcohol even in small amounts can have injurious effect18.

Ethanol consumption among pregnant women has found out to have damaging effect in

the central nervous system of the infant leading to impaired cognitive and behavioral function19.

In another recent study where the researchers determined the frequencies of different

neurodevelopmental disorders using a cohort study found out that that 9% among 71 children

who have mothers with prenatal alcohol exposure exhibits autism20. Nonetheless, the study did

not determine if there is an association between prenatal alcohol exposure and developing

autism. Furthermore, in this study, autism was only classified as a co-morbid of FAS or fetal

alcohol syndrome.

A case-control study explored the relationship between FASD (fetal alcohol syndrome

disorder) and ASD (autism spectrum disorder) in individuals attending a specialist diagnostic

clinic. The study found out that 72% of the subjects have autism and that therefore there is an

association between FASD and having ASD21.

Nonetheless, for both studies, it must be noted that only a small population was used

which may indicate that samples may not be a representative of the total population.

Furthermore, the focus of both studies was FASD and not ASD per se. Indicating that both

studies did not clearly state whether ASD was due to prenatal alcohol exposure or just a co-

morbid or a manifestation of FASD.

A study on “Autism families with a high incidence of alcoholism” results also showed an

association between prenatal alcohol exposure and autism13. Nonetheless, the researchers also

pointed out that there are no literatures or studies that distinctly indicate that alcohol exposure

among mothers can be associated to ASD simply because the incidence of alcoholism is so much

greater than autism that the sample size of children with autism should be larger in order to have

a valid association.

With this, it must be clear that the association of prenatal alcohol exposure (whether in

low or high doses) in developing ASD alone is not yet fully established.

Prenatal Smoking Exposure as a Risk Factor for ASD

Tobacco is considered one of the biggest environmental hazards in the world and it has

been widely established that prenatal maternal smoke exposure affects the mental development

of a child, including decreased cognitive functioning by 3 years old, decrease in vigilance in the

child and behavior problem22. However there are only a few sources that explore and focus on its

effects on the growth and development of the unborn child. A Swedish case-control study was

considered one the largest studies on perinatal risk factors of autism and one of the very few

studying maternal smoking and autism. Results showed that there was an association between

early pregnancy and daily smoking of the mothers (OR=1.4; CI = 1.1-1.8)14. This study is

considered one of the pioneering studies on perinatal risk factors of autism among the few

studies.

Additionally, children in utero who were exposed to smoking may exhibit cognitive

deficits such as delayed language development, difficulties in learning and memory tasks,

reading and mathematics, and decreased general cognitive functioning23. They concluded that

smoking in pregnancy may be a marker for increased risk of psychiatric symptoms in the

offspring. Scores in the Autism Spectrum Screening Questionnaires were significantly higher (p

< 0.001) for children born of smoking mothers compared to children born of non-smoking

mothers23. The researchers concluded that intrauterine and neonatal factors related to deviant

intrauterine growth or fetal distress is important in the pathogenesis of autism.

Studies that focus on the mechanisms regarding the specific effects of smoking to

prenatal development are numerous. Tobacco contains over 2000 chemical constituents, all of

which may induce neurotoxic effects such as decreasing cerebral blood and causing brain

hypoxia resulting to production of high levels of carboxyhemoglobin and relative brain

hypoxia24. Nicotine may affect a broad spectrum of neurotransmitter receptors in the fetal brain

leading to abnormal cell proliferation and differentiation as well as abnormal up-regulation and

down-regulation of neurotransmitter receptors25. Post-mortem studies on autistic subjects have

exhibited a notable reduction in cortical nicotinic receptor binding26. Moreover, other findings

have suggested that fetal nicotine exposure may affect brain development and 5HT synaptic

function linked with behavioral abnormalities27.

Hence, there is an evident need for additional studies that may provide more information

regarding the effects of maternal smoking on the development of autism among children owing

to the lack of sources.

CHAPTER 3.

METHODOLOGY

A. Study Design / Plan of Investigation

This study is a simple random sampling, case-control study. Cases are mothers with

children diagnosed with ASD. They will be obtained in the following manner. A list of

institutions, schools, and private clinics in Metro Manila (such as SHINE Intervention Center,

Circles and Triangles, Autism Society of the Philippines) will be compiled. Three institutions

will be randomly selected. A list of students per institution will then be obtained. Each institution

will be assigned a percentage of the sample size based on the number of students enrolled, and

cases will be selected via simple random sampling.

Controls will be mothers whose children are not diagnosed with ASD. They will be

related to or have the same characteristics (such as age, occupation, and socioeconomic status) as

the mothers of children with ASD. As such, they will be neighbors or workmates of the selected

cases.

Both cases and controls will be asked to answer a set of facilitated questionnaires

regarding demographic data, alcohol intake and smoking habits, before and during the period in

which they were pregnant with the autistic child. For alcohol intake, cases and controls will be

classified as chronic drinkers, non-chronic drinkers, and without exposure. For smoking, cases

and controls will be classified as having high pack years, low pack years, and without exposure.

Coding and encoding of the data gathered will proceed while data collection is still

ongoing. When sample size is achieved, data editing will proceed then followed by data analysis.

B. Scheme of the Study

C. Description of Study Group and Subjects

Cases are mothers of children diagnosed to have ASP by a licensed developmental

pediatrician. These children will be obtained from established autism societies primarily the

Autism Society of the Philippines (ASP) and other private clinics or institutions such as SHINE

Intervention Center and Circles and Triangles; all of these institutions are located in Metro

Manila. Special Education Division or SPED schools will also be a source of the cases. These

children should be within the age bracket of 4-11 years old at the time of implementation of the

study.

Controls will be mothers whose children are not diagnosed with ASD. They will be

related to or have the same characteristics (such as age, occupation, and socioeconomic status) as

the mothers of children with ASD. Suggested participants in the control group are work mates

and neighbors of mothers with autistic children; so that the characteristics and the environmental

conditions of both mothers will be the same.

Inclusion criteria are mothers of children ages 4-11 years old who are diagnosed to have

ASD by a board-certified developmental pediatrician and who are members of the Autism

Society of the Philippines or regularly go to special education clinics in Metro Manila. Minimum

child age is set as 4 years old since it is the median age at which a child is diagnosed to have

ASP; maximum age is set at 11 years old to prevent recall bias on the part of the mother.

Exclusion criteria include mothers with comorbid conditions such as psychiatric

disorders, illicit drug intake, or any hereditary disease. Children with ASD symptoms who are

diagnosed with other comorbid diseases such as Fetal Alcohol Syndrome and Down’s syndrome

will also be excluded.

D. Sample Size Estimation

Objective Specification Sample size estimate

To describe the association of smoking before or during pregnancy in

developing ASD among their children

To describe the association of alcoholism before or during pregnancy in developing ASD among their children.

p = 0.12d = 2.4

p = 0.09d = 1.8

(1.96) 2 (0.12)(0.88) (2.4)2

=14 (for each control and case group)

(1.96) 2 (0.09)(0.91) (1.8)2

= 19 (for each control and case group)

Total Population: 38 (case and control)

E. Data Collection Methods

The participants will be asked to answer a set of questionnaires (see Appendix A and B).

The researchers will be present during the time of collection so that any questions that the

participants may have can be accommodated. In addition to the questionnaire, the controls will

be also be asked to accomplish a screening checklist containing major DSM-IV criteria for the

diagnosis of ASP (see Appendix C). This is to ensure that the children of control mothers do not

have ASP.

The questionnaire or the data instrument that will be used will be formulated based on

literature review, key informant interviews (KII), and focused group discussions (FGDs). The

questionnaire will also be subjected to a series of pre-tests prior to implementation.

F. Operational Definition of Variables

Autism Spectrum Disorder: According to the Diagnostic and Statistical Manual of

Mental Disorders (DSM-IV, 1994), Autism Spectrum Disorder is composed of Autistic Disorder,

Asperger’s syndrome, and Pervasive Developmental Disorder. It is a group of developmental

disabilities that can cause significant social, communication and behavioral challenges.  It begins

before the age of 3 and lasts throughout life. Symptoms may not show until 24 months or later. A

person with an ASD might not respond to their name by 12 months of age, not be able to point at

objects, not play pretend play, they avoid eye contact and rather be alone, they have difficulty in

understanding other peoples feelings, they have delayed speech and language skills, they exhibit

echolalia wherein they repeat words and phrases over and over again, they give unrelated

answers in response to questions, they get upset with minor changes, they have obsessive traits,

flap their hands and rock their bodies28.

Social skills are the most common symptoms in all types of ASD. Examples of social

issues related to ASD’s are they do not share interests with others, only interacts to achieve

desired goals, has flat and inappropriate facial expression, does not understand personal space

boundaries, avoids and resists physical contact and is not comforted by others during distress.

Examples of communication issues related to ASDs are, delayed in speech and language skills,

they usually reverse pronouns (e.g they interchange me and I), uses no or a few gestures, talks in

a robot voice and does not understand jokes and sarcasm28.

People with ASD show unusual interests and behaviors. Examples of these are they like

lining up toys or other objects, they play with the same toys in the same way every time, they

like specific parts of objects, they are very well organized, follow certain routines. People with

ASD’s repeat actions over and over again which may involve one or more body parts. Repetitive

activities are know as self-stimulation or “stimming” They thrive in routine, once their routine is

broken they usually lose control and have tantrums28.

Other symptoms related to ASD are hyperactivity, impulsivity, short attention span,

aggression, temper tantrums, unusual eating and sleeping habits, unusual moods or emotion

reactions and lack of fear or more fear than expected28.

Smoking: defined as a practice in which tobacco is inhaled through cigarettes, expressed

in pack years. Pack years is equal to the number of cigarettes smoked per day, multiplied by the

number of years smoked, divided by 20.

o Low pack years: defined as mothers with pack years less than 5

o High pack years: defined as mothers with pack years greater than or equal to 5.

o No exposure: defined as mothers who have never smoked (pack years = 0).

Alcohol intake: defined as the consumption of any beverage containing ethanol, and may

include beers, wines, and spirits.

o Chronic alcohol drinker: defined as people who have dependency on alcohol

which includes strong craving for alcohol and inability to limit drinking. For

women, mostly defined as consuming an average of more than 1 drink per day.

o Non-chronic alcohol drinker: Includes moderate drinking and binge drinking.

o Moderate drinking: Defined as having no more than 1 drink per day

o Binge drinking: Defined as 4 or more drinks on a single occasion for

women, generally within about 2 hours.

G. Data Processing and Analysis

After gathering the data, data coding and encoding will proceed using Microsoft Excel

and by following a coding manual. Data editing will follow so as to inspect and correct some

errors during the pre-coding of the data.

Results will be analyzed using the odds ratio (OR). The formula for OR is as follows:

Odds Ratio = ad/bc

An OR = 1 will indicate no association between the outcome (development of ASD in

children) and exposure to the risk factor (smoking or alcohol intake during pregnancy). An OR >

1 will indicate the presence of an association (mothers with more exposure to smoking or alcohol

intake during pregnancy have a higher likelihood of having children with ASD). An OR < 1 will

indicate the presence of an inverse association (mothers with less exposure to smoking or alcohol

intake during pregnancy have a higher likelihood of having children with ASD).

To compute for the odds ratio, the following 2 x 2 tables will be used:

(+) autistic children (-) autistic children(+) smoking a b(-) smoking c d

(+) autistic children (-) autistic children(+) alcohol intake a b(-) alcohol intake c d

After computing the odds ratio, regression analysis will be done to determine which

among the maternal characteristics surveyed (such as age of pregnancy, number of children,

socioeconomic status, degree of alcohol intake, degree of smoking intake) contributed the most

to the development of autism among children.

H. Dummy Tables

Objective 1: To describe the socio-demographic characteristics of mothers of children (4-11 years old) with ASD according to:

Table 1. Socio-demographic characteristics of mothers of children with ASD

Characteristic Frequency Percentage

Age of mothers when they conceived their child with ASD

Below 18 years old 18 – 25 years old 26 – 35 years old 35 – 40 years old Above 40 years

old

Income Status High

Middle Low

Highest educational attainment

Elementary High School College

Marital Status Single Married Widowed

Objective 2, 3, 4 and 5: (2)To determine the prevalence of prenatal smoking exposure among mothers with and without children with ASD. (3) To determine the prevalence of prenatal alcohol exposure among mothers with and without children with ASD (4) To describe the association of smoking before or during pregnancy in developing ASD among their children (5) To describe the association of alcoholism before or during pregnancy in developing ASD among their children.

Table 2. Comparison of smoking and alcohol exposure between mothers with and without children with ASD.

Mothers with autistic children Mothers without autistic children

Frequency Percentage Frequency Percentage

Smoking

Without exposure:

With exposure:- High pack years- Low pack years

Alcohol

Without exposure:

With exposure:- Chronic alcoholic- Non-chronic alcoholic

CHAPTER 4.

TIMELINE AND BUDGET

A. Schedule of Activities

Weeks 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 201. Coordinating

with schools

2. KII interviews

3. Selection of participants for pre-testing

4. FGD for pre-testing of questionnaire

5. Editing questionnaire

6. FGD for final pre-testing of questionnaire

7. Final editing of questionnaire

8. Selecting cases

9. Data Collection for cases

10. Selecting Controls

11. Data Collection for controls

12. Data Processing

13. Data Analysis14. Writing of

paper

B. Budget

Items Amount (Pesos)Printing

- Ink- one ream of bond paper x 2- photocopy and binding (proposal and thesis presentation)- ball pens (2 boxes)

Subtotal

- 100- 500- 500

- 1001200

Transportation Fare 1000KII token 400Food

- First FGD; Pre-testing (moderator and 10 participants)- Second FGD; Pre-testing (moderator and 10 participants)

Subtotal

- 360

- 360

720Total 3320

C.

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Symptoms. Retreived on September 18, 2011 from http://www.cdc.gov/ncbddd/

autism/signs.html

APPENDIX A.

SAMPLE CONSENT FORM

University of the East Ramon Magsaysay Memorial Medical Center Inc. Department of Preventive and Community Medicine

College of Medicine

You are being invited to participate in the study entitled “A case-control study of smoking and alcohol intake as prenatal risk factors of Autism Spectrum Disorder (ASD) among Filipino children” under the supervision of Dr. Ramon Jason Javier. The following have been explained well to me and I fully understand them before I signed this consent form.

Ikaw ay inaanyayahan na lumahok sa pananaliksik na pinamagatang “A case-control study of smoking and alcohol intake as prenatal risk factors of Autism Spectrum Disorder (ASD) among Filipino children” sa pamamahala ni Dr. Georgina Paredes Ang mga sumusunod ay ipinaliwanag na mabuti sa akin at lubos ang aking pang-unawa sa mga ito bago ko nilagdaan ang kasulatang ito.

The objective of the study is to determine the association of exposure to prenatal risk factors, specifically smoking and alcohol intake, in developing Autism Spectrum Disorder among Filipino children.

Ang layunin ng pananaliksik ay upang malaman kung meron bang relasyon ang paninigarilyo o paginom ng alak sa panahon ng pagbubuntis sa pagkakaroon ng Autism Spectrum Disorder.

This study will be helpful to fill a gap in knowledge about the environmental causes of Autism, as well as lays the foundation for future researches in the Philippines.

Ang pananaliksik na ito ay makakatulong ng malaki sa pagkontribyuta ng mga pangunahing kaalaman sa kondisyon na Autism.

The number of study participants is 38.Ang bilang ng mga sasali sa pag-aaral na ito ay 38.

The study will involve a one page survey questionnaireSa pag-aaral na ito, kinakailangang sumagot ng isang pahinang survey questionnaire or

katanungan

All your records or information about you will be kept strictly confidential.Ang lahat ng iyong mga rekord o pangalan ay konpidensyal at hindi malalaman ng iba.

Your participation is voluntary and you can withdraw anytime for any reason. Ang pagsali mo sa pag-aaral na ito ay sarili mong kusa at maaari kang tumiwalag anumang oras

sa anumang kadahilanan.

You can call or ask questions anytime regarding this study. The contact person for further information or for consultation on diverse events is Sarah Jane A. Jimenez, 09052443580.

Maaari kang magtanong ng kahit anong oras hinggil sa pag-aaral na ito. Ang tatawagan at kakausapin ay si Sarah Jane A. Jimenez, 09052443580.

I gave my consent subject to the conditions above.Pumapayag akong sumali sa pag-aaral ayon sa mga nakasaad sa itaas.

SignatureLagda

________________________________ Participant Pastisipante

__________________________________ ______________________________ Witness Witness Saksi Saksi

__________________Date Signed:Petsa

Informed Consent obtained by: _______________________________________ Name and Signature

APPENDIX B.

SAMPLE QUESTIONNAIRE.

Control No._____

Birthday: _______ Age:___ Occupation:_______

Marital Status: Highest Educational Attainment: Single____ Elementary _____ Married ____ High school _____ Widowed____ College____

How many children do you have? _____

Directions: Please answer the following questions by checking the most truthful answer. Note that there are no right or wrong answers to all the questions.

1. Do you have a child diagnosed with Autism Spectrum Disorder (ASD)?___ Yes ___ No

If No, please go to number 5

2. What age was your child diagnosed with ASD? ___4-6 Years old___7-10 years old___10 and above

3. Which among your children was diagnosed with ASD? ____Eldest____Middle____Youngest

4. How old were you when you were pregnant with your child with ASD? ____ below 18 years old____ 18 – 25 years old____26 – 35 years old____35 – 40 years old____ above 40 years old

5. Have you ever smoked a cigarette? ____ Yes____ No

If No, please go to number 9.

6. How long have you been smoking? _____less than a year _____ 1-3 years_____4-6 years _____6-10 years_____10-20 years_____20 or more years

7. What age did you start smoking?______

8. On the average, how many cigarettes do you smoke per day?____ 1-2____3-5____6-10____10-20 (1 pack) ____20 or more

9. Do you drink any alcoholic beverage? ___ Yes___ No

If no, please go to number 14

10. How long have you been drinking alcoholic beverages? _____less than a year _____ 1-3 years_____4-6 years _____6-10 years_____10-20 years_____20 or more years

11. What age did you start drinking alcoholic beverages? _____

12. How often do you usually drink? ____ 1x a week____ 2 to 3x a week____Everyday ____Monthly____2-3 times a year

13. What kind of alcoholic beverages do you drink? Check all that applies

___Beer Per day, how many bottles do you drink? ___ 1 to 2 bottles ___ 3-6 bottles ___ 7 bottles

___Wine Per day, how many glasses do you drink? ___ 1 to 2 glasses ___ 3-6 glasses ___ 7 or more

___Hard liquor (Gin, Vodka, Tequila, etc.) ___1 to 2 shots ___3 to 5 shots ___ 5 or more shots

If your answer to question number 1 is NO; please disregard question 14 and 15.

14. Did you stop smoking when you were pregnant with your child with ASD? ___ Yes completely stopped___No, but smoked less than the usual ___No, did not changed smoking habit

15. Did you stop drinking alcoholic beverages when you were pregnant with your child with ASD? ___Yes, completely stopped___No, but drank less than the usual___No, did not changed drinking habit

***Thank you for your participation ***

APPENDIX C.

SCREENING CHECKLIST FOR CONTROLS.