Modular qualifications with assessment throughout a course do not bypass the stress and workload associated with linear "all or nothing" end-of-course exams, new research has found.
The study by Cambridge Assessment compared linear and modular GCSEs in maths and English.
"Modular assessment does not remove the stress and workload of an all or nothing exam," it concluded.
"Students of modular mathematics experienced longer periods of higher workload than linear students did in the first half of the year.
"For students of English, the workload varied considerably during the course of the year and there were no differences in linear and modular students' workload levels."
The research found that modular English GCSEs led to lower grades than linear ones once pupil ability was accounted for.
But in maths, candidates got higher grades through the modular route, once their ability had been taken into account.
Carmen Vidal Rodeiro, Cambridge Assessment senior research officer, said: "The simplistic 'all or nothing' approach to modularisation was wrong. Modularisation had a 'certain degree of trendiness' and was adopted without concrete proof that it improved standards.
"Our study clearly shows that there's justification for both assessment routes to co-exist."
The Government has given the go-ahead for all state schools to opt for linear IGCSEs in preference to modular GCSEs.
Michael Gove, Education Secretary, has also said he would like to see new linear A-levels developed to attract schools away from the modular approach and encourage a "revival of the art of deep thought".