The Philippine Institute for Development Studies (PIDS) has undertaken a key initiative to harmonize five decades of Philippine Census of Population and Housing (CPH) data, addressing long-standing inconsistencies that hinder effective policy analysis.
Aligned with its 2020–2025 research agenda, PIDS underscores the need for accurate and consistent statistical estimates to support evidence-based policymaking. The state think tank calls for a more responsive Philippine statistical system to meet the increasing demand for reliable data-driven decisions.
In its study titled “Harmonizing Philippine Census Data across Decades (1970–2020)”, authored by PIDS Supervising Research Specialist Kris Ann Melad, persistent challenges in achieving data consistency are examined. It highlights how discrepancies in variable definitions, classification schemes, and measurement scales complicate comparisons and risk misinterpreting trends. “[These inconsistencies] hinder accurate comparisons of data points, increasing the risk of misinterpretation and compromising the reliability of longitudinal analyses,” Melad explained.
The Philippine Statistics Authority (PSA) conducts the CPH every five years, collecting vital demographic and housing information. This comprehensive survey includes data on age, sex, education, and housing characteristics such as construction materials and occupancy. Government agencies depend on this data to guide resource allocation, craft targeted policies and programs, and plan for local and national development. Similarly, the private sector uses census data for market research and investment planning, making the CPH an essential tool for understanding the country’s population, socio-economic conditions, and development trajectory.
However, inconsistencies in data standards across census periods pose significant challenges to accurate analysis. To address these issues, the study seeks to reconcile these discrepancies, enabling more reliable longitudinal analyses and strengthening the foundation for evidence-based policy research.
Key challenges highlighted in the study include shifts in educational categories due to the K–12 curriculum reforms, updated occupational classifications to reflect emerging industries, and the introduction of new administrative regions, which necessitated adjustments to location codes. Earlier censuses with fewer variables and the complexities of digitizing historical data further complicate harmonization efforts.
To enhance the dataset’s usability, the study recommends prioritizing the recovery and digitization of census data from 1970 and 1980, which would strengthen historical analysis. It also calls for the development of detailed links between classification systems—such as those for occupations, industries, and education—along with thorough documentation of how these categories have evolved over time. A historical geographic reference system is also proposed to track changes in administrative boundaries since 1970, facilitating more precise geographic comparisons.
The study underscores the need for clear guidelines to assist researchers in effectively using the dataset, including strategies for addressing missing or inconsistent data. Additionally, it advocates for continuous refinement to expand scope, incorporate user feedback and ensure long-term relevance and reliability.
“The implementation of these recommendations will enable the Philippine Statistical System to provide increasingly robust and well-documented data for longitudinal analysis,” Melad concluded.
Read full study at https://bit.ly/pidsdp2024-44 to understand the methods and insights. ###
