Week 5.1 Health Indicators, Demography and Population estimation.pdf

Health Indicators, Demography, Population Estimation  Health Indicators Tools used to measure objectively a specific health concept of interest Usually numeric measures which help compare the targeted or expected results of health programs  Types of Health Indicators...

Health Indicators, Demography, Population Estimation  Health Indicators Tools used to measure objectively a specific health concept of interest Usually numeric measures which help compare the targeted or expected results of health programs  Types of Health Indicators According to: 1. aspect of health being measured 2. group referred to 3. time covered by the events 4. components of the evaluation framework  1. According to the aspect of health being measured Health status indicators – measure health outcomes and/or their risk factors Health service performance indicators – measure aspects of the performance of health services or public health programs  2. According to the group referred to Crude rates – describes the total population which is used as the denominator in the computation Specific rates – describes only a specific sub-group of the total population being considered  Examples Crude death rate (CDR) Age-specific death rate (ASDR)  3. According to the time covered by the events Point in time – occurred during the specific point in time being considered Period of time – occurred over a period of time  Examples Prevalence Number of existing cases in a place at a given time = x 100 Number of existing cases in 4 place at a given time Incidence Number of new cases occuring in a place in a given period of time = x 100 Number of new cases occurring in a place in a given period of time 4. According to the components of the evaluation framework Input indicators – resources needed to deliver the essential services to the population or to achieve project objectives Output indicators – direct products of project activities. Generally in the form of activities and processes undertaken Outcome indicators – immediate result of the services or activities implemented Impact indicators – intended or unintended long-term organizational/community changes  Type of Indicator Indicator Input -Number of posters and brochures on family planning -Number of community volunteers trained to conduct health education Output -Number of couples who have seen or received the posters -Number of health education classes conducted Outcome -% increase in the level of knowledge among couples on family planning -% increase in number of family planning acceptors Impact -decrease in the average number of children per family -decrease in the population growth rate  Conventional Health Status Indicators Measures of Morbidity Measures of Mortality Measures of Fertility  Computing Indicators Absolute numbers Ratios Proportions Rates  Computing Indicators Absolute Numbers simple count of the number of persons, houses or events being considered easy to understand but difficult to interpret especially when making comparisons among groups with different sizes Cases of measles of schoolchildren in Provinces A and B Province Number of measles cases of schoolchildren A 450 B 200 Province Number of measles cases Total number of % of school children of schoolchildren schoolchildren infected with measles A 450 800 56.25% B 200 250 80.0% Ratio result of dividing one number by another reserved for measures wherein the numerator is not part of the denominator – example: sex ratio Proportion special kind of ratio wherein the numerator is part of the denominator When multiplied by 100 – called as percentage – example: % of infants who are full immunized % of households with sanitary toilets Rate measures how fast an event occurs over time or space expressed in terms of the frequency of occurrence of events common example in health is the incidence rate of a disease. Formula for Rate, Ratio and Proportion ! = x k " – a: # of persons or events being considered – b: size of the group to which the number in the numerator is being related to – k: factor (100, 1000, 10000, 100000 or even 1M) To make the resulting number easier to interpret  Demography The scientific study of human populations – Population size – Population structure/composition – Population distribution in space “Study of the size, territorial distribution, and composition of the population, changes therein, and the components of such changes” Hauser and Duncan (1959:2)  A. Population Size Affected by: – Natality – Mortality – migration 2 Methods of Population Allocation A. De Facto Method: people are counted or allocated to the area where they were physically present at the time of the census B. De Jure Method: people are counted or allocated to the place of their usual residence  B. Population Composition Determines the number of percentage of the population according to the categories of important socio-demographic-economic variables The most basic description of the population composition is according to age and sex.  Factors Affecting Population Composition Birth rate: # of births per 1000 population Death rate: # of deaths per 1000 population Emigration: number of people leaving a country Immigration: number of people moving to a country  Describing the Age Composition of a Population Median Age: the age below which we have 50% of the population Age dependency ratio: indicator of age-induced economic drain on human resources – Children (0-14yo) – Elderly (≥65yo) – Computed as the ratio of the dependents to the economically active group (15-64) of the population  Describing the Sex Composition of a Population Sex ratio: computed by dividing the number of males by the number of females using a factor of 100 Interpreted as the number of males for every 100 females in the population  The Population Pyramid Graphical presentation of the age and sex structure of a population Special type of histogram: male population is shown at the left and females at the right – Youngest age group is the base and the oldest is the top Either the actual population count or he percentage of the population can be graphed.  C. Population Distribution Description of how people are distributed in a specified space or geographic area Affected by: – Physical – Political – Social/Cultural – Economic Indicators: – Population density – Crowding index  Population Estimation Computation of future changes in population numbers, given certain assumptions about future trends in the rates of fertility, mortality and migration  Purposes of Population Estimates For analysis of various trends For measuring shifts in population For determining allocation of public funds or political representation in the government For planning  Measures of Changes in Population Size A. Natural increase B. Rate of natural increase C. Relative increase D. Absolute increase per year (b) E. Annual rate of growth (r) A. Natural Increase Natural increase in a specific place and time = number of births – number of deaths Example: – Determine the natural increase in 2017 Year 2017 Births 1,761,602 Deaths 531,280 1,761,602 – 531,280 = 1,230,322 B. Rate of Natural Increase Rate of natural increase in a specific place and time = crude birth rate (CBR) – crude death rate (CDR) natural increase expressed as rate C. Relative Increase Actual difference between 2 census counts expressed in percent relative to the population size of the prior census Relative increase Pt – P0 = P x 100 0 P0 = population size at an initial time, time 0 Pt = population size at time t D. Absolute Increase per year (b) Measures the average number of people added to the population per year Pt – P0 b= t P0 = population size at an initial time, time 0 Pt = population size at time t t = number of years between time 0 and time t  Estimating Relative and Absolute Increase Compute for the following given the data below: – Relative increase from 2010 – 2013 – Absolute increase per year from 2010 – 2013 Year Population 2010 92, 337,852 2013 98,393,574  Estimating Relative and Absolute Increase Year Population Relative Increase 2010 92, 337,852 Pt – P0 2013 98,393,574 = x 100 P0 Absolute increase Pt – P0 b= t E. Annual Rates of Growth (r) Also utilize results of 2 censuses to quantify the amount of change in population size Assumes that the population is changing at a constant rate per year  Method of Estimation Take into account all the operations that can affect population size Component Method Mathematical Method  A. Component Method Also known as inflow-outflow or balancing equation method Pt = Po + (B – D) + (I – O) – B: births in the interval 0 and t – D: deaths in the interval 0 and t – I: immigration between 0 and t – O: out-migration between 0 and t  B. Mathematical Method Arithmetic method: assumes equal change every year Geometric method: assumes that the population changes at the same rate over each unit Exponential method: assumes a constant rate of change (r) and population is increasing continouosly  Estimating Rate of Change (r) Exponential r = In (Pt / P0) / t x100 – Pt : future population – P0 : past population – t: time elapsed  Estimating Future Population (Pt) Exponential Pt = P0 ert – P0 : past population – t : time elapsed – r : rate of change – e : constant equivalent to 2.71 Estimating Past Population (P0) Exponential Pt P0 = rt e Estimation of the amount of time (t) Exponential In (Pt /Po) t= r  Example Given below is the Philippine census information in 1995 and 2000. Using the data, estimate the following: 1. Rate of change 2. July 1, 2005 population 3. December 25, 1997 population 4. time to reach 100, 000, 000 population Year 1995 2000 Census date Sept. 1, 1995 May 1, 2000 Population 68, 616, 538 76, 504, 077 LB 1, 766, 440 1, 645, 043 Deaths 324, 737 366, 931 CBR 25.74/1000 21.50/1000 CDR 4.73/1000 4.80/1000 Thank you…