There have been multiple research studies done on and around the alphabetic principle.

A case study on preschoolers found that there are is a high correlation between letter writing and name writing, and that writing scores were related to letter-sound identification. This relates to the alphabetic principle because as children get older and move through their elementary years, letter-sound identification is the foundation to success. Children must be able to recognize letters and know their sounds before being able to write successfully. This is just another way to look at the importance of teaching the alphabetic principle

Another study was done that researched the link between name writing and emergent literacy knowledge. This study asked the question, what does a child’s written representation of his or her own name tell us about emergent literacy knowledge in print and phonological awareness? The study found that the name writing ability reflects children’s skills in other literacy areas. It appears from the study that name writing supports emergent literacy development.

Worden and Boettcher did a study; it examined the development of critical aspects of alphabet knowledge. The aspects it studied were letter recitation, naming, printing, and the association of letters and sounds. Trained examiners tested children of ages 3 to 7. The study revealed valuable teaching information. When asked to recite the alphabet, children at age three could on average not recite more than five letters but by age 5 could on average recite almost all the letters. Children between ages four and five could name a high amount of uppercase letters but struggled with lowercase letters. Lowercase letter naming did not improve until around six to seven years of age. In the print tests, it showed that the largest gains in printing ability took place between ages three to six. Children were more comfortable printing uppercase letters. The sound and word tasks were scored, showing the biggest gain in ability being between five to seven years of age. This is important to know because teachers are able to target these areas for improvement.

Molfese, V. J., Beswick, J. L., Jacobi-Vessels, J. L., Armstrong, N. E., Culver, B. L., White, J. M., . . . Molfese, D. L. (2010, September 25). Evidence of alphabetic knowledge in writing: Connections to letter and word identification skills in preschool and kindergarten. Reading and Writing, 24(2), 133-150. doi:10.1007/s11145-010-9265-8

Welsch, J., Sullivan, A., & Justice, L. (2003). That’s My Letter!: What Preschoolers’ Name Writing Representations Tell Us about Emergent Literacy Knowledge. Journal of Literacy Research, 35(2), 757-776. doi:10.1207/s15548430jlr3502_4

Worden, P., & Boettcher, W. (1990). Young children’s acquisition of alphabet knowledge. Journal of Literacy Research, 22(3), 277-295. doi:10.1080/10862969009547711