Ara decans

• The material was prepared by Calixto S. Sabela Jr., Department of Medical Technology, College of Nursing, Cavite State University for the use of students enrolled in MEDT 05 - Biostatistics and Epidemiology.
• The material is for the use of students enrolled in MEDT 05 - Biostatistics and Epidemiology.
• The material is not to be distributed without permission.
• The learning objectives of the session are to explain the principles of sampling and its purpose, differentiate probability and non-probability sampling, and identify the steps of the different probability sampling designs.
• Sampling is the act of studying or examining only a segment of the population to represent the whole.
• Whatever findings we get for this segment of the population, we generalize to the total population.
• The advantages of sampling include being cheaper, faster, and providing better quality of information.
• A smaller group of sample requires only a smaller number of data collector who can be trained more rigidly and supervised closely.
• A hospital is a cluster of employees.
• In multi-stage sampling, the population is first divided into a set of primary or first-stage sampling units (PSUs), then samples of such units are selected.
• In two-stage cluster sampling, the first stage involves listing all the clusters in the population, and the second stage involves selecting units in the clusters.
• In multi-stage sampling, the procedure continues until the desired stage is reached.
• Multi-stage sampling involves sampling in more than one stage.
• A census block is a cluster of households.
• A class is a cluster of students.
• Cost considerations in cluster sampling include the number of clusters, the size of the sample, and the number of elements in each cluster.
• In two-stage cluster sampling, only a subset of sampling units in the cluster are selected.
• In single-stage cluster sampling, all sampling units in a cluster are selected.
• A smaller group allows the use of more complicated and accurate technical methods, which are often expensive and time-consuming.
• Sampling provides more comprehensive data as it allows for detailed questions on some topic.
• Sampling is the only possible method for destructive methods such as blood sample collection for RBC and WBC count.
• Census is a complete enumeration of all items in the population.
• Sampling population in sampling is the population from which a sample will actually be taken.
• Basic concepts in sampling include population, target population, sampling population, sampling frame, sampling unit, and elementary unit.
• Sampling unit in sampling is the units which are chosen in selecting the sample and may be made up of non-overlapping collection of elementary units/units.
• Target population in sampling is the group from which representative information is desired and to which inferences will be made.
• Population in sampling is the entire group of individuals or items of interest in the study (people, medical record, biological vector, rural health units, houses, etc.).
• Sampling in public health is used for evaluating the health status of a population, estimating the magnitude or extent of health problems and conditions through prevalence survey, investigating factors affecting health, and evaluating the effectiveness of health measures.
• Finite population in sampling is a population containing a finite number of items (vs Infinite).
• Homogeneous population in sampling means that elementary units have similar characteristics (vs heterogeneous).
• Elementary unit in sampling is the object or person on which information is actually taken or observation is made.
• Sampling frame in sampling is a sort of listing or any other material like maps or aerial photographs, which shows the target population and is a collection of all the sampling units.
• Sampling is used to gather information about large populations, save money, save time, and when it's impossible to study the whole population.
• Census involves a great deal of time, money, and energy.
• Census is difficult to apply because of the resources involved.
• Undertaking a census survey is not possible in many cases.
• Sometimes it is possible to obtain sufficiently accurate results by studying only a part of the total population through sampling.
• Select a random start which can be any number from 1 to k (Random start: 2).
• Cluster Sampling is a probability sampling method in which each sampling unit is a collection or cluster of elements, which are close together.
• In a study to determine the proportion of children in Brgy X with BCG immunization, the sampling frame is the list of all children living in Brgy X.