An education select committee report into the impact of testing pupils raises concerns that the regular publication of SATs results is putting pressure on teachers and negatively impacting on the quality of learning in primary schools.
It calls for the publication of annual Key Stage 2 test results to be scrapped in favour of a three-yearly public release, with only schools having access to yearly data.
The report states: "Assessment is closely linked to the accountability system in primary schools, with Key Stage 2 results used to hold schools and teachers to account on the progress and attainment of pupils. However, the high-stakes system can negatively impact teaching and learning, leading to narrowing of the curriculum and ‘teaching to the test', as well as affecting teacher and pupil wellbeing."
The committee is also concerned that Ofsted is putting too much focus on SATs results, which only cover maths, reading and writing, and wants to see the inspectorate look more at the broader curriculum, especially how well science is being taught.
Committee chair Neil Carmichael said: "Many of the negative effects of assessment in primary schools are caused by the use of results in the accountability system rather than the assessment system itself.
"The resulting high-stakes system has led to a narrowing of the curriculum with a focus on English and maths at the expense of other subjects like science, humanities and the arts.
"It is right that schools are held to account for their performance but the government should act to lower the stakes and help teachers to deliver a broad, balanced, and fulfilling curriculum for primary school children."
Dr Mary Bousted, general secretary of the Association of Teachers and Lecturers, described primary school testing as "critically flawed".
She added: "It is important that schools are accountable for the learning and wellbeing of their pupils, but the current narrow assessment system is not fit for purpose. The core role of assessment should be to support teaching and learning, we hope that the incoming government will seek to make this the priority."
The committee is also critical of baseline assessments for reception age children.
These were introduced in primary schools in England in 2015 but in April last year the government ditched plans to use them as a starting point for measuring pupil progress as they were "not sufficiently comparable". The government indicated at the time that it was looking for an alternative replacement.
"We support the introduction of an improved progress measure, but the government must be cautious if a baseline measurement is introduced. It should be designed as a diagnostic tool to help teachers identify pupils' needs and must avoid shifting negative consequences of high-stakes accountability to early years," states the report.
Pre-school Learning Alliance chief executive Neil Leitch backed the committee's concerns.
He said: "Aside from being an unreliable and limited method of assessment, baseline testing puts unnecessary pressure on children at the beginning of their formal educational journey.
"At this important stage of a child's life, we should be focusing on fostering a love of learning and supporting their development, not using them as a way to rank and measure schools.
"We believe that any early assessments should be observation-based, informed by early years experts and focused on supporting children's learning and development."