The 2008 Annual Poverty Indicators Survey (APIS) is conducted by the National Statistics Office (NSO) as a rider to the July 2008 Labor Force Survey (LFS). The 2008 APIS is the sixth in the series of annual poverty indicators surveys conducted nationwide. Since 1998, APIS has been conducted during the years when the Family Income and Expenditures Survey (FIES) is not conducted, except in 2001 and 2005 due to budgetary constraints.
The APIS is a nationwide survey designed to provide non-income indicators related to poverty at the national and regional levels. It is designed to gather data on the socio-economic profile of families and other information that are related to their living conditions. Specifically, it generates indicators which are correlated with poverty, such as indicators regarding the ownership or possession of house and lot, the types of the materials of the roofs and walls of their housing units, their access to safe water, the types of toilet facility they use in their homes, and presence of family members of specified characteristics such as children 6-12 years old enrolled in elementary, children 13-16 years old enrolled in high school, members 18 years old and over gainfully employed, working children 5-17 years old and family members with membership in any health, life and/or pre-need insurance system.
The APIS is being undertaken by the National Statistics Office as mandataed by Commonwealth Act 591 which authorizes the then Bureau of the Census and Statistics, now NSO, "to conduct by enumeration, sampling or other methods, for statistical purposes, studies of the social and economic situation of the country" and in consonance with the provision of Executive Order 121 which designated the office as the "major statistical agency responsible for generating general purpose statistics.
Kind of data
Sample survey data [ssd]
Unit of analysis
v1.0: Edited data, first version, for internal use only
economic conditions and indicators [1.2]
Seventeen (17) Administrative Regions:
National Capital Region (NCR)
Cordillera Administrative Region (CAR)
I - Ilocos
II - Cagayan Valley
III - Central Luzon
IVA - CALABARZON
IVB - MIMAROPA
V - Bicol
VI - Western Visayas
VII - Central Visayas
VIII - Eastern Visayas
IX - Zamboanga Peninsula
X - Northern Mindanao
XI - Davao
XII - SOCCSKSARGEN
XIII - Caraga
Autonomous Region in Muslim Mindanao (ARMM)
Unit of analysis
The survey covered all households.
Producers and sponsors
Government of the Philippines
National Statistical Coordination Board
The 2008 APIS is a sample survey designed to provide data representative of the country and its 17 administrative regions. The survey's sample design helps ensure this representativeness. The 2008 APIS used the 2003 master sample created for household surveys on the basis of the 2000 Census of Population and Housing (CPH) results. The survey used four replicates of the master sample. For each region (domain) and stratum, a three-stage sampling scheme was used: the selection of primary sampling units (PSUs) for the first stage, of sample enumeration areas (EAs) for the second stage, and of sample housing units for the third stage. PSUs within a region were stratified based on the proportion of households living in housing units made of strong materials, proportion of households in the barangay engaged in agricultural activities and per capita income of the city/municipality.
As earlier mentioned, a three-stage sampling design was used in each stratum within a region. In the first stage, primary sampling units (PSUs) were selected with probability proportional to the number of households in the 2000 Census. PSUs consisted of a barangay or a group of contiguous barangays. In the second stage, in each sampled PSU, EAs were selected with probability proportional to the number of households in the 2000 Census. An EA is defined as an area with discernable boundaries consisting of approximately 350 contiguous households. In the third stage, from each sampled EA, housing units were selected using systematic sampling. For operational considerations, at most 30 housing units were selected per sample EA. All households in sample housing units were interviewed except for sample housing units with more than three households. In such a housing unit, three households were randomly selected with equal probability.
The 2008 APIS was conducted simultaneously with the July 2008 Labor Force Survey (LFS). All sample households of the July 2008 LFS were interviewed for the 2008 APIS. Only household members related to the household head by blood, marriage or adoption were considered as members of the sample household in APIS. Family members of the household head who are working abroad were excluded.
Deviations from sample design
Of the 43,020 eligible sample households for the 2008 APIS, 40,613 were successfully interviewed. This translated to a response rate of 94.4 percent at the national level. Households which were not interviewed either refused to be interviewed or were not available or were away during the enumeration period.
The results presented in this report are weighted to ensure that the data are representative of the population of the Philippines and its regions. Sampling weights, or expansion factors, were applied to the data obtained from sample households in order to derive estimates for the larger population from which the sample households were selected for the purpose of survey interviewing. The weights or expansion factors applied to each sample household reflected the probability of the households being selected for the survey sample. More specifically, the basic sampling weights assigned were equal to the inverse of the joint probability of selection in the three stages of sample selection. Since the sample was self-weighting within regions (domains) or strata, each household in a particular stratum received the same weight, or raising factor.
The weights adjustment factor takes into account the sample EAs which were not enumerated and households which were not interviewed. The product of the basic weights and weights adjustment factor was used to obtain the preliminary weighted estimates of the total number of families.
In order to make the weighted estimate of the total number of persons by age group and sex consistent with the estimated number of persons by age group and sex as of July 2008, a final weight adjustment factor was used. The estimated number of persons by age group and sex, by region as of July 2008 was derived using 2000 Census-based population projection for the region. In each region, the final weight adjustment is equal to the ratio of the estimated number of persons by age group and sex as of July 2008 to the preliminary weighted estimate of the total number of persons by age group and sex from the 2008 APIS data.
Dates of collection
Mode of data collection
Data collection supervision
The Regional Directors (RDs) or the Regional Statisticians, the Provincial Statistics Officers (PSOs) or their Provincial Statisticians was provided with 5 mandays each for supervision. The District Statistics Officer (DSO) who was designated as the Provincial Over-all Supervisor was responsible for all interviewing teams in the province. He/She supervised during the entire duration of the APIS fieldwork. In general, one Team Supervisor (TS) was assigned to supervise three Statistical Researchers (SRs).
Selected Central Office Statisticians also supervised the field operation in the Regional and Provincial Offices.
The role of the supervisors include the following:
a) Observing some of the interviews to ensure that interviewers are conducting themselves well, asking the questions in the right manner, and interpreting the answers correctly;
b) Spot check some of the addressed selected for interviewing to be sure that interviewer interviewed the right household;
c) Review each questionnaire to be sure it is complete and is internally consistent;
d) Meet with each member of the team on a daily basis to discuss performance and give out future work assignments;
e) Help interviewers to solve any problems that he/she might have with finding the assigned households, understanding the concepts in the questionnaire or with difficult respondents
Though questions on 'Changes in Welfare' were dropped and some items were modified for the 2008 APIS, most of the questions/items in the previous APISs were retained as requested by data users. Nine items were added in order to generate data that will be more useful in assessing the poverty situation in the country. The new questionnaire for the 2008 contains the abridged version of the module on entrepreneurial activities resulting to the reduction of the number of pages from 24 to 12. The decision to use the abridged version was based on the results of the study entitled “Redesigning APIS as a Poverty Monitoring Tool” undertaken by the Demographic and Social Statistics Division in 2006. The redesigned questionnaire produced results which are not statistically different from results based on the original design in 2004. The use of the redesigned questionnaire is also cost-efficient.
A round table discussion was held for the 2008 APIS before the conduct of the pretest. The redesigned APIS questionnaire based from the project's output was presented. It was agreed upon during this meeting to adopt the redesigned APIS for this round of APIS, with the addition of item on 'Hunger'.
National Statistics Office
Flow of Processing Activity
In order to implement a systematic flow of the processing activities and reduce the movement of questionnaires from one employee to another, the same processor performed the following specific activities for the same folio.
1. General screening;
2. Editing and coding of APIS questionnaires and computations of totals ; and
3. General review of edited APIS questionnaire.
To facilitate handling during manual and machine processing, APIS questionnaires were folioed in the Provincial Office before the start of manual processing.
The APIS questionnaires for one sample barangay/EA contained in the folio was arranged consecutively according to the sample housing serial number (SHSN) from lowest to highest.
General screening was done by going over the submitted accomplished questionnaires and checking for the completeness of the geographic identification and other information called for in the cover page.
General screening for APIS questionnaires was done to ensure that the geographic and household identification and the entire sample households are the same with the MS Form 6.
General Instructions on Manual Processing
The following instructions was observed in manual processing.
1. Prior to editing and coding of items, the questionnaires were checked if they were properly folioed. Folioing was done in the province. Regional Offices checked if folioing was done properly by the Provincial Offices.
2. All questionnaires for one folio was assigned to only one editor/coder, unless otherwise necessary (e.g., when the one who is processing a folio is absent for more than a day).
3. In general, the editors assumed that the original entries are correct. Editing was done only when an entry is obviously incorrect. A doubtful or inconsistent item was verified in the field.
Other forms of data appraisal
A series of data quality tables were generated to review the quality of the data and include the following:
- Age distribution of the household population
- Highest grade completed versus current grade
- Highest grade completed versus age
- Current grade versus age
- Reason for not attending school versus highest grade completed
- Reason for not attending school versus current grade
- Marital status versus age
- Consistency of income vs. expenditure
Authorization to use this data is granted only to the client or data user and persons within its organization, if applicable. Under no circumstances shall the client reproduce, distribute, sell or lend the entire data or parts thereof to any other data user apart from himself or that of authorized employees in his organization. The NSO shall hold the data user fully responsible for safeguarding the data from any unauthorized access or use.
Before being granted access to the dataset, all users have to formally agree:
1. To make no copies of any files or portions of files to which s/he is granted access except those authorized by the data depositor.
2. Not to use any technique in an attempt to learn the identity of any person, establishment, or sampling unit not identified on public use data files.
3. To hold in strictest confidence the identification of any establishment or individual that may be inadvertently revealed in any documents or discussion, or analysis. Such inadvertent identification revealed in her/his analysis will be immediately brought to the attention of the data depositor.
Any report, paper or similar articles, whether published or not, emanating from the use of this data shall give appropriate acknowledgement as suggested herein, “(Title of Census/Survey, version number and date), National Statistics Office, Manila, Philippines”, as the source of basic data. The data user or client is encouraged to provide NSO with a copy of such report, paper or article. It is understood that unless expressly allowed by the client, such report, paper or article shall not be used for any purpose other than monitoring.
Disclaimer and copyrights
The NSO gives no warranty that the data are free from errors. Hence, the NSO shall not be held responsible for any loss or damage as a result of the client's manipulation or tabulation of the data.
The data user acknowledges that any available intellectual property rights, including copyright in the data are owned by the Philippines National Statistics Office.
National Statistics Office-Demographic and Social Statistics Division