The scope of an LDS is not limited to the K–12 grade levels. Indeed, the value of longitudinal data is even greater when it spans beyond these years into early childhood and postsecondary education, and the workforce. Systems that span these years are commonly referred to as "P–20" systems.*
For years, many states have been collecting student-level data on publicly funded pre-kindergarten (PK) and early childhood education (ECE) programs for students with special needs. These data typically include information on which services were received and where. However, few states have child-centered data systems that track enrollment or participation in private PK or ECE programs or daycare centers. As policy and education discussions expand to address P–20 longitudinal data systems and the impact of educational opportunities across the full spectrum of learning, more education stakeholders are trying to understand the relationship between early childhood learning and kindergarten- or grade school-readiness, and subsequent performance.
"As states and school systems work to align expectations in high school with the demands of postsecondary education, they need better data on (students who) leave the P–12 system and enter college (and other postsecondary programs). Most states today do not have data systems that enable this two-way communication. With the ability to match student records between P–12 and (postsecondary education), policymakers and educators would know:
With a connection between education and workforce data, researchers can answer questions about whether schools, colleges, and universities are preparing students for long-term success in the workplace, what percentage of students graduating from a district or school is unemployed one year after graduation, and how a graduate's earnings are related to academic preparation in high school. (DQC 2007, Linking Education and Social Services Data to Improve Child Welfare)