The phrase "a previous step" is correct and usable in written English.
It can be used when referring to an earlier action or stage in a process or sequence of events.
Example: "Before proceeding to the next phase, please review a previous step to ensure all requirements are met."
Alternatives: "an earlier step" or "a prior step".
In any computation, the next step will often depend on the result of a previous step.
Cells were disrupted at high pressure and then freeze-dried as a previous step to extraction.
And a previous step to ban beer vendors in the bleachers failed to cut down on the incidents.
Vacancy creation could be considered as a previous step to the formation of active sites for catalytic oxidation.
For the regression model, the VIV response at a previous step is also involved as an additional input variable.
The benefits of using cement paste or mortar tests as a previous step in SCC design to optimize mixture proportions have been recognized.
In this sequential optimization, the objective value obtained in a previous step is added as an additional constraint to the next step.
An irreversible bonding of phenol on the catalyst surface has been found as a previous step to the phenol oxidation reaction.
The results obtained have been used to propose several hypotheses about the likely key process variables that require a better control, as a previous step to conducting further studies for process diagnosis and optimisation, like experimental designs.
The objective of this work is to propose a method for identifying soft-biometrics, in the form of clothing and gender, from images containing people, as a previous step for further identifying people themselves.
In order to reduce both the amount of catalyst needed for incineration and the surface area of recuperative heat exchangers, an evaluation of the use of thermal swing adsorption as a previous step for VOC concentration is made.
