Even though many curricula include some elements of effective instruction, this does not mean they are necessarily effective. Direct Instruction (capitalized), the programs developed by Siegfried Engelmann and colleagues, incorporates all of these elements. Other direct instruction (no capitals) curricula incorporate only some of the effective elements.
Siegfried Engelmann, the founder of Direct Instruction, and Geoff Colvin, Ph.D., a longtime collaborator, have developed a rubric for identifying authentic DI programs - ones that conform to all of the elements of effective instruction. See Rubric for Identifying Authentic DI Programs
A key element of effective instruction is ensuring that students master the material they are studying. This is often called "mastery learning." In a 1999 article, Engelmann describes how teaching to mastery involves aligning student needs and the content of a curriculum and shows how DI programs accomplish this. See Student-Program Alignment and Teaching to Mastery
An article by Cheryl Schieffer and colleagues, published in 2002, shows how one DI program, Reading Mastery, embodies the elements of effective instruction. Schieffer et al, JODI, vol. 2, no. 2, pp. 87-119