By Tess Stynes 
 

National chain-store sales edged up a 0.2% in the first three weeks of April from the comparable period in March, according to Redbook Research's latest indicator, released Tuesday.

The index's increase compared with a target for growth of 0.8%.

The Johnson Redbook Sales Index also showed seasonally adjusted sales for the period improved 1.1% from a year earlier, compared with a target for an increase of 1.7%.

During the third week of April, sales rose 1.4% from a year earlier.

Redbook noted the latest week was the last in which distortion related to a shift in the Easter holiday will occur, allowing retailers a clearer view of their underlying businesses.

Write to Tess Stynes at tess.stynes@wsj.com